Because of problems with my e-mail, I had to send this letter once more in order to reach all recipients of the mailing list; sorry. Bernd Hess *************************************************************** **** **** **** ESF Programme **** **** **** **** RELATIVISTIC EFFECTS IN HEAVY ELEMENT CHEMISTRY **** **** AND PHYSICS **** **** **** *************************************************************** Newsletter No. 29 (March 24, 1998) ______________________________________________________________ Editor: Bernd Hess, hess@uni-bonn.de Tel. 49-228-732920 FAX 49-228-732551 ______________________________________________________________ The programme 'Relativistic Effects in Heavy-Element Chemistry and Physics' ('REHE') has been initiated by the European Science Foundation in November 1992 and ran for 5 years, i.e. from 1993 through 1997. The programme was intended to strengthen the indicated "field" and to facilitate interactions between European scientists concerned with related topics. Apart from a few activities approved in 1997 and deferred to 1998, the programme expired end of 1997. The 'steering committee' is now preparing the final report for the European Science Foundation. The 'Steering Committee' of the programme has at present the following members: E. J. Baerends (Amsterdam) J.P. Daudey (Toulouse) K. Faegri (Oslo) I.P. Grant (Oxford) B. Hess (Bonn, Vice-Chairman) J. Karwowski (Torun) P. Pyykko (Helsinki, Chairman) K. Schwarz (Vienna) A. Sgamellotti (Perugia) C. Werner (ESF). ================================================================================ --- E D I T O R I A L Dear collegues, for the final report to the European Science Foundation, we have prepared a list of 'papers funded by REHE'. We should like to include in this list all those papers with REHE mentioned in the acknowledgement. This list is now in the www, linked to the REHE newsletter pages at http://pcgate.thch.uni-bonn.de/tc/hess/esf/nl.html I should appreciate very much if you could visit this list and notify me about any papers that should be included. Please, include the number of the corresponding REHE project. Please send this information at your earliest convenience (by email) to hess@uni-bonn.de and send me a reprint for those papers which are not mentioned. ------------------------------------------------------------------------- The next newsletter (#30) is scheduled for June 1998. Please send material >by e/mail< that enables us to fill the following topics in forthcoming newsletters All REHE newsletters are available on www under URL http://pcgate.thch.uni-bonn.de/tc/hess/esf/nl.html see also the URL of the European Science Foundation http://www.esf.c-strasbourg.fr ================================================================================ --- R E S E A R C H N E W S AND R E L A T E D I N F O R M A T I O N Summaries of recent research or comments to it (up to 1 page), which are of general interest to the 'REHE' community, may be submitted by any colleague preferrably by E-mail to my attention. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ [communicated by Andreas Savin] Report on WENJIAN LIU's stay at the Laboratoire de Chimie Theorique (CNRS) Universite Pierre et Marie Curie, Paris Sept. 21 to Oct. 15, 1997 (REHE No. 23-97) The visitor worked in Paris from September 21 to October 15, 1997 The purpose of this visit was to discuss the possibilities of including an explicit treatment of non-dynamic correlation within a relativistic framework in the BDF (Beijing 4-component density functional) code. Two possible ways were taken into consideration. The first one is to use information which is easily provided by density functional codes, like the procedures proposed by Ziegler or by Becke, Savin and Stoll. The second approach needs explicit evaluation of two-electron integrals. (Their replacement by density functional expressions, along the lines proposed by Ziegler or by Savin, Stoll and Preuss was also discussed.) While exploratory atomic calculations were already performed during the visit, the computation of new integrals needs a more serious modification of the BDF code and will be pursued in future. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ================================================================================ --- C O N F E R E N C E N E W S 'Conference News' (in general they should NOT overrun about 1 page) may be provided by organizers or their scientific secretaries. -- For meetings and workshops supported by ESF the submission of such a report is a m u s t . To facilitate my job the reports should be forwarded to my attention via E-mail. Also please send information about conferences that might be of interest for the members of the REHE community. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ [communicated by Martin Kaupp] Conference announcement/reminder (update March 1998): ---------------------------------------------------------------------------- CONFERENCE ON "Quantum Chemical Calculations of NMR and EPR Parameters" Bratislava (castle Smolenice), Slovakia, on 14 - 18 September, 1998. ---------------------------------------------------------------------------- Major Topics Include: --------------------- Quantum chemical studies of nuclear shielding tensors, spin-spin coupling, nuclear quadrupole coupling, hyperfine coupling, electronic g-tensors List of speakers (up to now): ------------------------------------------ V. Barone (Napoli, Italy) R. J. Bartlett (Gainesville,USA) M. Buehl (Zuerich,Switzerland) D. M. Chipman (Notre Dame,USA) S. Colwell (Cambridge,UK) H. Ebert (Muenchen, Germany) B. Engels (Bonn,Germany) L. A. Eriksson (Stockholm, Sweden) R. R. Ernst (Zuerich,Switzerland) J. C. Facelli (Salt Lake City,USA) U. Fleischer (Bochum, Germany) J. Gauss (Mainz,Germany) C. J. Jameson (Chicago,USA) S. Karna (USAF,USA) P. Lazzeretti (Modena, Italy) G. H. Lushington (Columbus, USA) F. Mauri (Lausanne, Switzerland) P. Pulay (Fayetteville,USA) W. T. Raynes (Sheffield, UK) K. Ruud (Oslo,Norway) D. R. Salahub (Montreal, Canada) N. M. Sergeyev (Moscow, Russia) E. van Lenthe (Amsterdam, The Netherlands) L. Visscher (Amsterdam, The Netherlands) P. von R. Schleyer (Erlangen,Germany) K. Schwarz (Wien, Austria) R. E. Wasylishen (Halifax,Canada) J. Weber (Geneva,Switzerland) T. Ziegler (Calgary,Canada) ------------------------------------------ Organizing Committee -------------------- V.G. Malkin (Bratislava,Slovakia) (Chair) M. Kaupp (Stuttgart,Germany) International Scientific Committee ------------------------------------ W. Kutzelnigg (Bochum,Germany) J. Oddershede (Odense,Denmark) P. Pyykko (Helsinki,Finland) W.T. Raynes (Sheffield,UK) J.A. Tossell (Maryland,USA) ---------------------------------------------------------------------------- More information with continuous updates, as well as preliminary registration forms are available on the conference web pages: http://www.theochem.uni-stuttgart.de/~mkaupp/smolen.html http://www.savba.sk/sav/inst/uach/smolen.html To receive the official second circular (probably in April 1998), preliminary registration should be completed by e-mail to NMR98@savba.sk or by regular mail to: NMR-EPR-98 Institute of Inorganic Chemistry Slovak Academy of Sciences Dubravska Cesta 9 SK-84236 Bratislava Slovak Republic ---------------------------------------------------------------------------- NMR-EPR-98 Conference, Bratislava PRELIMINARY REGISTRATION FORM Name:................................................................. .....................(First Initial Last ); Title:.................... Institution:.......................................................... ...................................................................... Address:.............................................................. ...................................................................... ...................................................................... ...................................................................... Country:.............................................................. ...................................................................... Phone:................................................................ ...................................................................... FAX:.................................................................. Email:................................................................ Scientific contribution (tentative title):............................ ...................................................................... ############################################################################ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ [communicated by Jacek Karwowski] REHE WORKSHOP ON SPIN-ORBIT COUPLING IN CHEMICAL REACTIONS Institute of Physics, Nicholas Copernicus University, Torun, Poland January 24 -- 27, 1998 The workshop was held at the Institute of Physics of the Nicholas Copernicus University in Torun. It was concerned not only with theoretical methods and computational details, but also with qualitative findings of SOC manifestations in spectra and reactivity of molecules. The conceptual importance of SOC effects in chemistry has been emphasized in many contributions. There were 18 oral contributions and 18 posters presented during the meeting. All contributions discussed various aspects of relativistic effects in atoms and in molecules. About 60% of them were concerned with spin-orbit-coupling-related phenomena. The remaining ones addressed various aspects of relativistic theory of atoms and molecules ranging form formal considerations on Dirac-Coulomb Sturmians to presentations of results of specific calculations. Since the meeting was intended to be partly a school, there were several tutorial talks and the research talks contained rather broad tutorial introductions. One of the aims of the meeting was to create of an opportunity for an exchange of ideas between scientists from the Western Europe and their colleagues from the former Soviet Union Countries. There were 40 scientists participating in the meeting. Out of them 9 came from the former Soviet Union (Estonia, Latvia, Russsia, Ukraine), 22 from the Central Europe (Czech Republik, Poland, Slovakia) and 9 from the Western Europe (Belgium, Finland, France, Germany, Sweden). The total budget of the workshop was 40 000.- FRF. A financial support has been given to all participants from the former Soviet Union, from the Czech Republic, from Slovakia and to the invited speakers (all together to 20 participants). Jacek Karwowski --------------------------------------------------------------------------------- LIST OF PARTICIPANTS Maria Barysz Torun, Poland teomjb@chem.uni.torun.pl Eugeniusz Bednarz Torun, Poland eugeneb@phys.uni.torun.pl Dorota Bielinska-Waz Torun, Poland dsnake@phys.uni.torun.pl Miroslaw Bylicki Torun, Poland mirekb@phys.uni.torun.pl Elena Chomenko Cherkassy, Ukraine akin@bee-pitron,cherkassy.ua Ruvin Ferber Riga, Latvia ferber@acad.latnet.lv Alexander Glushkov Odessa, Ukraine synop@ogmi.odessa.ua Wlodzimierz Jaskolski Torun, Poland wj@phys.uni.torun.pl Jacek Karwowski Torun, Poland jka@phys.uni.torun.pl Vladimir Kelloe Bratislava, Slovakia kelloe@nic.fns.uniba.sk Jacek Kobus Torun, Poland jkob@phys.uni.torun.pl Konrad Koc Krakow, Poland sfkoc@cyf-kr.edu.pl Roman Kozlowski Olsztyn, Poland kozrom@tufi.wsp.olsztyn.pl Marek Krosnicki Gdansk, Poland kro@disneyland.mif.pg.gda.pl Sven Kruger Muenchen, Germany krueger@theochem.tu-muenchen.de Dorota Kulaga Krakow, Poland dorota@dekan.wsp.krakow.pl Svetlana Malinovskaya Odessa, Ukraine synop@ogmi.odessa.ua Uko Maran Tartu, Estonia uko@chem.ut.ee Christel Marian Bonn, Germany cm@sfb334.thch.uni-bonn.de Laurent Maron Toulouse, France tei@irsamc1.ups-tlse.fr Jan Micanko Bratislava, Slovakia micanko@theochem.chtf.stuba.sk Boris Minaev Cherkassy, Ukraine boris@ifm.liu.se Valentina Minaeva Cherkassy, Ukraine Jan Najbar Krakow, Poland najbar@trurl.ch.uj.edu.pl Elena Pazyuk Moscow, Russia elena@laser.chem.msu.su Grzegorz Pestka Torun, Poland gp@phys.uni.torun.pl Pekka Pyykkoe Helsinki, Finland pekka.pyykko@helsinki.fi Carl Ribbing Leuven, Belgium carl.ribbing@chem.kuleuven.ac.be Szczepan Roszak Wroclaw, Poland roszak@kchf.ch.pwr.wroc.pl Andrzej Rutkowski Olsztyn, Poland andrut@tufi.wsp.olsztyn.pl Andrzej Sadlej Torun, Poland teoajs@chem.uni.torun.pl Bernd Schimmelpfennig Stockholm, Sweden bernds@physto.se Jozef Sienkiewicz Gdansk, Poland jes@mif.pg.gda.pl Monika Stanke Torun, Poland samuel@phys.uni.torun.pl Andrey Stolaryov Moscow, Russia avstol@laser.chem.msu.su Michal Straka Brno, Czech Republik straka@cis.vutbr.cz Radek Szmytkowski Gdansk, Poland radek@mifgate.mif.pg.gda.pl Christian Teichteil Toulouse, France tei@irsamc1.ups-tlse.fr Juha Vaara Oulu, Finland jvaara@sun3.oulu.fi Joachim Werner Stuttgart, Germany werner@theochem.uni-stuttgart.de ------------------------------------------------------ LECTURES; M. Barysz (Torun): Relativity by perturbation theory: Effects of inacuracies in the reference function R. Ferber (Riga): Spin-orbit coupling effects in spectra of Te2 molecule. J. Karwowski (Torun): Introduction to the relativistic theory of many-electron systems. V. Kelloe (Bratislava): Electron correlation and relativistic effects in calculations of electric properties of atoms and molecules C. Marian (Bonn): The performance of the spin-orbit mean-field approximation in molecular calculations L. Maron (Toulouse): The mean-field SO-method with ECPs B. F. Minaev (Cherkassy and Link"oping): The role of one-center spin-orbit coupling model in organic chemical reactions B. F. Minaev (Cherkassy and Link"oping): Spin-orbit coupling effects in NMR, ESR and UV molecular spectroscopy J. Najbar (Krakow): Heavy atom effects in the relaxation of excited aromatic molecules in rigid and fluid systems P. Pyykkoe (Helsinki): Relativistic effects in the chemistry of heavy elements. C. Ribbing (Leuven): SOC in 3d element photochemistry. S. Roszak (Wrocl{}aw): Spin-Orbit Configuration Interaction Study of the Electronic Spectrum of IO A. Rutkowski (Olsztyn): Direct perturbation theory for strongly interacting molecular states A. Sadlej (Torun): Two-component approximations in relativistic theories. B. Schimmelpfennig (Stockholm): The mean-field SO-method: Theory and applications J. Sienkiewicz (Gdansk): Spin-orbit interaction in electron-heavy atom collisions". R. Szmytkowski (Gdansk): The Dirac-Coulomb Sturmian functions H.-J. Werner (Stuttgart): Ab initio study of SOC effects in molecular spectra and reaction dynamics. ____________________________________________________________________________________________ POSTERS: (in parentheses are names of the coauthors who do not participate in the meeting) A. V. Glushkov Relativistic density-functional theory based on quantum electrodynamics for multielectron systems A. V. Glushkov (with S. V. Ambrosov, T. V. Buyadgi, A. V. Efimov) SOC effects in spectra of Rydberg resonances for heavy elements in electric field A.V.Glushkov (with A.F.Kivganov and V.A.Efimov) Heavy elements, relativistic-soc effects in catalysis processes A.V.Glushkov (with Yu.A.Kruglyak, V.D.Parkhomenko, P.N.Tcybulev, A.S.Katashinsky) Relativistic DFT calculations of heavy elements clusters A.V.Glushkov, S.V.Malinovskaya (with I.Shpinarev and S.Danko) Spin-orbit effects in electron satellites spectra production in intense laser field on nuclei in atom, ion and molecule: relativistic and QED approaches A.V.Glushkov, S.V.Malinovskaya (with L.A.Vitovetskaya) Ground and excited states of alkali dimers: potential curves with spin-orbit coupling G. I. Kobzev and B. F. Minaev Collision-induced singlet-triplet transitions in molecular oxygen K. Koc (with M. J. Vilkas and Y. Ishikawa) Quadratically convergent multiconfiguration Dirac-Fock and multireference relativistic configuration interaction calculations for many-electron systems R. Kozlowski and A. Rutkowski Double perturbation approach to the relativistic hydrogenic atom in magnetic field D. Kulaga (with J. Migdalek) Relativistic effects in Ba S. V. Malinovskaya (with V. N. Polischuk and V. N. Orlova) Relativistic calculation of Ne-and Ar-like multicharged ions: SOC effects L. Maron, B. Schimmelpfennig and Ch. Teichteil (with H. Fagerli, O. Gropen and U. Wahlgren) SOC and relativistic effects in transition metal-, actinide- and gold-compounds L. Maron, C. Teichteil Influence of the all-electron relativistic reference atomic calculations on the SO pseudopotentials splittings L. Maron, C. Teichteil A test on the validity of a two-step relativistic method for molecules containing heavy elements J. Micanko (with S. Biskupic) Systematic generation of generally contracted relativistic Gaussiam basis sets V. A. Minaeva, B. F. Minaev (with O. Homenko) Spin-orbit coupling effects in ozone synthesis and photodissociation. M. Straka and V. Kell"o Model compounds of borane with Zn, Cd, and Hg. Correlated Douglas-Kroll calculations. J. Vaara (with K. Ruud, O. Vahtras, H. AA gren, and J. Jokisaari MCSCF quadratic response calculation of the electronic spin-orbit contribution to nuclear shielding tensors ------------------------------------------------------------------------------- ABSTRACTS: ORAL CONTRIBUTIONS ------------------------------------------------------------------------------ Relativity by perturbation theory: Effects of inacuracies in the reference function Maria Barysz Department of Quantum Chemistry, Faculty of Chemistry, N. Copernicus University, Gagarina 7, PL-87 100 Torun, Poland The first order relativistic corrections to energies can be determined either from the direct perturbation expansion of the Dirac equation or by using the so-called Pauli operator. The two formulae are equivalent for the exact non-relativistic reference functions but lead to different results for approximate solutions. The analysis of a model problem with controlled deviation from the exact non-relativistic solution clearly shows a preference for the first-order relativistic energy formula derived from direct perturbation theory. The use of the Pauli approximation with inaccurate non-relativistic reference functions may introduce significant inaccuracies in the calculated relativistic corrections for low-lying s-states. -------------------------------------------------------------------------------- Spin-Orbit Coupling Effects in the Spectra of Te_2 Molecules R. Ferber Department of Physics, University of Latvia, Riga LV-1586, Latvia The Te_2 molecule is a convenient test object of a heavy dimer, free of hyperfine structure for an even isotope and possessing a Hunds case (c) coupling scheme because of strong spin-orbit interaction. A complex experimental study of such Te_2 characteristics as energetic (term values, level shifts), radiative (lifetimes, relative intensities in laser induced fluorescence), magnetic (values and signs of Lande factors, magnetic field induced alignment-orientation conversion, magnetic predissociation) have been used, in the unified approach, for deperturbation treatment, as well as to determine the power and type of intramolecular interactions, in particular, spin-orbit (SO) coupling effects. The main semiempirical approach in evaluating the SO coupling parameters is based upon empiric fitting procedure in expanding (c) -- case wavefunctions over (a) -- case basis. The following particular examples are considered. The measured Lande factor value allowed to clarify that the thoroughly studies 1_{u state of rm Te_{2 is an admixture of 86% B, 3Sigma-_{1 and 14% A, 3Pi_{1 states mixed by SO coupling. The measured ratios of parallel electric dipole transition moments allow to evaluate the ratios of respective SO mixing constants. The measured spin-forbidden B, 3Sigma-_{u - b, 1Sigma+_{g transition dipole moment allows to pass to X, 3Sigma-_{g sim b , 1Sigma+_{g SO mixing constant. In all cases experimental and semiempirically estimated SO parameters, based on leading electronic configuration, are compared. Finally, experimental B, 1_{u state lifetimes are analysed in order to evaluate the SO effect caused predissociation reaction rate. [1] E. A. Pazyuk, A. V. Stolyarov, M. Ya. Tamanis, and R. S. Ferber, J. Chem. Phys. 99, 7873 (1993) [2] M. Auzinsh, A. V. Stolyarov, M. Tamanis, and R. Ferber, J. Chem. Phys. 105, 37 (1996) ------------------------------------------------------------------------------ Introduction to the relativistic theory of many-electron systems J. Karwowski Instytut Fizyki, Uniwersytet Mikolaja Kopernika, Torun, ul. Grudzic{adzka 5, 87-100 Torun, Poland A brief introduction to the relativistic theory of atoms and molecules is given. In particular, the Dirac equation for a single particle, its general properties, a transition to the nonrelativistic limit and generalizations of the formalism to the many-electron case are presented. Computational cosequences of the unboundensss from below of the Dirac spectrum and of singularities of the Pauli operator are discussed. The origin of the spin-orbit interaction and its influence on spectra and on other atomic and molecular properties are briefly analyzed. ------------------------------------------------------------------------------- Electron correlation and relativistic effects in calculations of electric properties of atoms and molecules Vladimir Kelloe Department of Physical Chemistry, Comenius University, SK-84215 Bratislava, Slovakia In the talk will be presented and analyzed results of calculations of electric properties of atoms and molecules. Electron correlation effects were accounted for at different levels of the approximation, varied from the simplest MBPT2 one up to the sophisticated Coupled Cluster methods with singly, doubly, and triply (noniterative or iterative) excitations included. Relativistic effects were treated within the Mass-Velocity-Darwin (MVD) or Douglas-Kroll (DK) schemes. The calculations were focused on heavy atoms with the atomic number up to 87 and small molecules formed by these heavy atoms. Dipole moments, dipole polarizabilities, ionization potentials and electron affinities results will be presented. A special part will be be dedicated to "molecular" calculations of nuclear quadrupole moments. --------------------------------------------------------------------------- On the Performance of the Spin-Orbit Mean-Field Approximation in Molecular Calculations Christel Marian GMD - National Research Center for Information Technology, St. Augustin, and Theoretical Chemistry, University of Bonn, Germany It is shown that the recently developed spin-orbit mean-field Hamiltonian [1] yields reliable results for heavy element compounds and for light mole-cules. For the transition metal compounds Pd_2, PdCl, and PtH a further simplification, i.e. neglecting the multi-center contributions to the spin-orbit coupling matrix element, can be applied without loss. In these cases it is possible to transfer the mean-field integrals to a molecular orbital basis from an effective core potential calculation [2]. This is not necessarily true for light molecules, where the percentage error of the one-center approximation can be considerable. For the twist and syn-pyramidalization modes of ethene contributions of one-center one-electron and two-electron terms are found to cancel only partially, depending on the C--C bond distance [3]. [1] B. A. He{ss, C. M. Marian, U. Wahlgren, O. Gropen, Chem. Phys. Letters 251 (1996) 365 [2] C. M. Marian, U. Wahlgren, Chem. Phys. Letters 251 (1996) 357 [3] D. Danovich, C. M. Marian, T. Neuheuser, S. D. Peyerimhoff, and S. Shaik, JPC A, submitted ---------------------------------------------------------------------------- The Mean-Field SO-method with ECPs Laurent Maron1, Christian Teichteil1, Bernd Schimmelpfennig2, Ulf Wahlgren2, Hilde Fagerli3 and Odd Gropen3 1I.R.S.A.M.C, Universite Paul Sabatier, 31062 Toulouse Cedex, France; 2Institute of Physics, University of Stockholm Stockholm, Sweden; 3Institute of Mathematical and Physical Sciences, University of Tromso, N-9037 Tromso, Norway Due to the arbitrary definition of the inner part of the nodeless orbital, solutions of the ECP calculations, the problem of the SO calculation had been solved by introducing a pseudo- operator acting on those nodeless orbital (pseudoorbital). We define a new way of extracting pseudopotentials from multiconfigurationnals 4-component calculations and we generalize the use of iterated natural orbital for the SO calculations. We present spectroscopic results on halogen atoms and molecules in very good agreement with experiment. Another solution, we propose, is to transfer the So integrals directly from a all-electron mean-field calculation to an ECP one. Even though the AE and ECP basis set are rather different, we define a one to one correspondence of the SO integrals. --------------------------------------------------------------------------- The role of one-center spin-orbit coupling model in organic chemical reactions Boris F. Minaev Institute of Physics and Measurement Technology University of Link"oping, S-58183, Link"oping, Sweden Spin-orbit coupling (SOC) at the intermediate stages of reactions determines chemical routes of many thermal and photo-processes through the control of nonadiabatic single t-triplet (S-T) transition probability. The S-T crossing normally occures at the intermadiate biradicaloid geometry and SOC has often been analysed by qualitative consideration of the two-centre SOC integrals in such biradicaloids. The shortcomings of this approach are briefly discussed here. The role of the one-centre SOC model, well known from molecular spectroscopy, is stressed and illustrated by few typical examples of bitopic reactions of oxygen containing molecules. SOC in the cleaved oxirane biradical is used as a simple introductory example, which is already studied by ab initio calculation. Previously analysed dioxetane thermolysis and the Paterno-B{"uchi photoreaction are accomplished here by some new details. Interpretations of the S-T transitions by the one centre SOC model are presented here for the O(3P) atom addition to aromatic substances, for photoisomerization of furans a nd of cyclohexa-2,5-dienones, and for the alpha-cleavage of carbonyl compounds. Analysis of the S-T potential energy surfaces crossings obtained by quantum chemical calculations and by correlation diagrams is generalized and augmented by vibronic perturbation for some reactions. It is shown that vibronic perturbation is important for SOC analysis in acyl-alkyl biradicals. --------------------------------------------------------------------------------- Spin-orbit coupling effects in NMR, ESR and UV molecular spectroscopy Boris F. Minaev Cherkassy Engineering and Technological Institute, 257006, Cherkassy, Ukraine Spin-orbit coupling (SOC) is one of the most important intrinsic magnetic perturbations in molecules and its role in phosphorescence and in ESR spectra is well known fo r a long time. Development of response theory for MC SCF formalism stimulated a great progress in ab initio studies of the singlet-triplet transitions probability and g-factor calculations in ESR spectra. The importance of SOC for NMR spectra of heavy elements have been recognized many years ago and studies of SOC contribution to NMR chemical shift by modern ab initio techiques is getting popular just recently. The proposed talk is devoted to calculation of SOC effects in NMR, ESR and optical spectra on the ground of response MC SCF formalism and includes the following: 1. Calculations of nuclear magnetic shielding parameters in the ground singlet and in the trip let excited states, the singlet-triplet (S-T) transitions probabilty, electronic and nuclear spin-rotational coupling constants, hiperfine coupling and g-tensors in the triplet state. Simultaneous calculations of all these SOC-depending properties (together with nuclear quadrupole resonance parameters in the S and T states) at th e same level of accuracy (the same basis set, CAS) permit us to make a proper assignments in interpretation of spectra. At the same time this help to understand connections between NMR, ESR, (NQR) and optical properties of molecules. 2. Calculations of the internuclear distance dependence for all these spin-dependant parameters and assignment of vibrational state dependence. 3. The following molecules will be considered: a. H_2O, H_2S, H_2Se. b. HOCl, HOBr, HOJ. c. HF, HCl, HBr, HJ; FCl, FBr d. O_2, S_2, Se_2, Te_2, SO, SeO, TeO, SSe, SeTe e. OCl, OBr, OI, OCl-, OBr-, OI-. f. O_3, NO_2-. g. H_2C=O, H_2C=S, H_2C=Se. i. Pyrazin. 4. The following results are discussed: (3.a.) In a series of molecules H_2X (3.a) a large deviation in NMR chemical shift (delta_ H) have been observed for X = Se. Preliminary semiempirical calculations have shown that it could be explained by SOC account. Large scale ab initio calculations are necessary for a proper explanation of this trend. At the same time the internuclear distance dependence of the delta_H chemical shift is predicted, since the triplet excited state of the molecule H_2X is getting the ground state in the dissociation limit H_2 + X(3 P). Calculations of SOC matrix elements along the reaction coordinate help us to understand photodissociation dynamics and to predict the triplet state properties of these molecules including the T-S transition intensity. (3.b.) Calculation of the S-T transition probability in these series is important for atmospheric photochemistry, since it can explain a new path of production of very reactive radicals OH + Br, I. (3.c.-e.) SOC calculations in these series has fundamental importance for many branchs of modern spectroscopy and photodissociaton dynamics. Connections with NMR and ESR parameters perform new criteria of spectroscopic assignments which could be equally important in optical and in radiofrequency regions. (3.f.) Triplet states of nitrite ion are well studied by optical detection of magnetic resonance (ODMR) and by ENDOR techniques. The old calculations of the hyper-fine interaction (HFI) tensor and g-tensors toge ther with radiative lifetime of the triplet state spin-sublevels were proving very usefull for ODMR assignment. The ENDOR measurements provides very rich information about fine, hyper-fine and NQR staructure of the lowest T state. It is interesting to perform new ab initio calculations of all these parameters of spin-hamiltonian and compare them with the ground state NMR and NQR properties. The S-T transition intensity provides an additional important criterion of the accuracy of SOC account. For isoelectronic ozone molecule the lowest triplet state (3A_2) has two minima on potential energy surface. The prediction of the S-T transitions probability has been latter supported by many experimental techniques. These findings raise a number of questions about the triplet ozone species in the atmosphere: is it formed and if so, how? What is its concentration? Can it be detected? Does it react with other species? In adressing these questions we are going to perform claculations of all spin-hamiltonian parameters for the low-lying triplet states of ozone 3A_2, 3B_2 and 3B_1 and also chemical reactivity of these states which expected to be the SOC dependent. (3.g.-i.) Studies of SOC effects in these molecules have general importance for molecular spec troscopy. 5. Internal and external heavy atom effects in NMR spectra of the ground state molecule, in ESR and in optical spectra (including optical detection of magnetic resonance) of the triplet excited state molecules are studied simultaneously. 6. Discovery of "spin-current" nature of molecular oxygen magnetic phosphorescence (the b1Sigma_g+- X3Sigma_g- transition or the atmospheric A oxygen band) made in the framework of semiempirical approach, has been completely supported later by sophisticated ab initio methods. The main idea of this approach is proven very useful in explanation and predictions of solvent induced intensity in oxygen spectra and in spin dependent oxygen reactivity. The lowest excited a1Delta_g state is highly metastable; its radiative lifetime at zero pressure limit is more than one hour. The probability of the a - X transition is determined by the electronic orbital angular momentum contribution to magnetic dipole transition moment and is extremely sensitive to collisions. The radiative lifetime of the a1Delta_g state diminishes by 3--4 orders of magnitude upon collisions in solvents and in the dense gases. An observed lifetime of the a1Delta_g state is mainly determined by non-radiative quenchin g in solvents. Nevertheless the singlet a1Delta_ g state oxygen emission is the main direct tool for monitoring this important metastable and chemically active intermediate. The a1Delta_g state, now often referred to as ``singlet oxygen, has been shown to be important in many applications, and particularly in biochemistry, including the mechanisms of certain human diseases, cell aging and laser cancer treatment. Photosensitized oxidation plays an important role in oxidative damage because natural cells constituents such as porphyrins or flavins can act as sensitizers. The research in this line will be continued in the project, including chemical activity of higher excited states A3Delta_u, A3Sigma+_u and B3Sigma-_u. These efforts in the project will be united with ozon photochemistry studies with account of SOC effect. Study of new spin-forbidden channels of ozon formation and degradation would be important for atmospheric chemistry and for environment sciences. Some intermediates produced by atomic and molecular oxygen reactions with unsaturated hydrocarbons and with radicals will be studied. So the project is devoted mainly to spin-orbit coupling effects in NMR spectra of heavy molecu les, in ESR spectra of radicals and triplet state excited species. Some applications to ozone depletion mechanisms and to other processes in atmosphere photochemistry are expected. --------------------------------------------------------------------------------- Heavy atom effects in the relaxation of excited aromatic molecules in rigid and fluid systems Jan Najbar Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow, Poland Relaxations of the excited states of aromatic molecules in solutions containing heavy atoms involve many different configurations of the flourophore and the perturbing molecules [1]. The lattice models of binary or multicomponent solutions and the binomial or multinomial distribution functions represent very effective tools allowing for averaging various photophysical quantities. The application of the generalized multinomial distribution functions for the derivation of the decay functions of the populations of the excited states of aromatic molecules and the decay functions of the luminescence are discussed. The approach can be applied to the description of the transient kinetics in a variety of situations. They include systems having different geometrical dimensions and structures (surfaces, zeolites, micellar systems and homogeneous fluid solutions). The diffusion limitations for the relaxation multilevel systems in the presence heavy atoms and electron transfer processes originating from initially excited states are considered. Possible generalizations of Wilkinson-Medinger equation for rigid and fluid solutions are also considered. The rare gas matrices (Ar, Kr, Xe) are very convenient systems for the study of the external heavy atom effect on the photophysical processes in organic molecules [2]. The phosphorescence spectra of naphthalene-h8 and -d8 molecules isolated in rare gas matrices show multiple sites with different couplings between aromatic molecule and rare gas matrix. Apart from spectral shifts an anisotropy of the spin-orbit-coupling for the phosphorescence decays of benzene--Kr in mixed Ar--Kr matrices are observed. The positional dependencies of the relaxation constants of the triplet states of chloro- and bromoquinolines show the contributions due to the vibronic couplings, the energy gap dependencies and the spin-orbit couplings. The correlation between the decay rate constants of the triplet states and the results of INDO calculations seem to indicate the importance of the charge transfer states for the internal heavy atom effects in halogeno substituted aromatic compounds [3]. The decays of the singlet and triplet states of aromatic compounds in the presence of halide ions (Br--, I- or CNS-) show different enhancements of the radiative and nonradiative transitions [1,4]. The external heavy atom effects in these systems involve additional electron transfer processes originating from the singlet excited states [5,6].[4pt] [1] J. Najbar, J. B. Birks, T. D. S. Hamilton, Chem. Phys. 23 (1977) 281 [2] J. Najbar, A. M. Turek, T. D. S. Hamilton, J. Lumin. 26 (1982) 281 [3] W. Jarzc{eba, J. Najbar, J. Cioslowski, J. Mol. Struct. 141 (1986) 469 [4] J. Najbar, M.Mac, J. Chem. Soc. Faraday Trans. 87 (1991) 1523 [5] J. Najbar, M. Boczar, A. M. Turek, Chem. Phys. 167 (1992) 37 [6] M. Mac, J. Najbar, J. Wirz, J. Photochem. Photobiol. A: Chem. 88 (1995) 93 ------------------------------------------------------------------------------- Relativistic effects in the chemistry of heavy elements P. Pyykkoe (Helsinki) ------------------------------------------------------------------------------- SOC in 3d element photochemistry C. Ribbing (Leuven) ------------------------------------------------------------------------------ Spin-Orbit Configuration Interaction Study of the Potential Energy Curves of IO S. Roszak Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wyb. Wyspianskiego 27, 50-370 Wroclaw, Poland Neutral IO is formed in the reaction of iodine with ozone, resulting in the destruction of ozone in the troposphere. Because of that the kinetics and mechanisms of reactions involving IO are studied by a number of laboratories. The calculations of the potential energy curves of IO are performed in three steps. The SCF calculation for IO+ produces molecular orbitals which are used in the standard multireference single and double-excitation CI method. The final step in the present method is to employ nonrelativistic eigenfunctions as basis for the final spin-orbit calculations. The electronic states corresponding to I(2P_u) and O(3P_g) at the dissociation limit have been considered. ----------------------------------------------------------------------------------- Direct perturbation theory for strongly interacting molecular states A. Rutkowski Institute of Mathematics and Physics, Pedagogical University, ul. .Zol nierska 14, PL-10561 Olsztyn, Poland Direct Perturbation Theory (DPT) for relativistic effects is generalized to the case of a set of near-degenerate strongly interacting states. This situation, where the standard approach breaks down, is quite common in atoms and especially in molecules. DPT consist of a partitioning of the Dirac equation into a four-component part equivalent to the Sch"odinger equation and a perturbation [A. Rutkowski, J. Phys. B bf 19, 149, 3431, 3443 (1986); W. Kutzelnigg, Z. Physik D bf 11, 15 (1989);D bf 15, 27(1990)]. The partitioning of the Hamiltonian itself is the same as in the perturbation approach formulated earlier by R.A. Moore [Can. J.Phys. bf 53, 1240, 1247, 1251 (1975)], but DPT contains also a partitioning of the metric, as first suggested by G.L. Sewell [Proc. Cambridge phil. Soc. bf 45, 631 (1949)] and later advocated for by Kutzelnigg. Recently [A. Rutkowski and W.H.E. Schwarz, J. Chem. Phys. bf 104, 8546 (1996)] we have proposed a simple alternative partitioning of the Dirac Hamiltonian which does not contain a change of the metric and which is especialy convenient for constructing the Bloch equation for the Mo ller wave operator Omega. (the final formulas, however, are independent of path of derivation). An effective Schr"odinger-like equation within a nonrelativistic model space of near-degenerate states is derived. The effective Hamiltonian and metric operators are expressed with the help of a Mo ller wave operator Omega, which generates the complete four-component Dirac wavefunction from the nonrelativistic Schr"odinger wavefunction in the finite model space. Explicit formulae are derived for different orders of h_{eff and s_{eff. They can be used to determine the relativistic energies to different orders either directly by diagonalization, or by a perturbation approach. Numerical results for groups of excited potential curves of the one-electron quasimolecule Sn99+_{2 and some one-electron two-center model systems are presented and discused. --------------------------------------------------------------------------------- Two-component approximations in relativistic theories A. J. Sadlej Department of Quantum Chemistry, Faculty of Chemistry, N. Copernicus University, Gagarina 7, PL-87 100 Torun, Poland Different ways of reducing the 4-component formalism to that of 2-component spinors, are considered. The consequences of the 2-component approximations derived by unitary transform methods are studied. Particular attention is given to the evaluation of expectation values iand transition properties. --------------------------------------------------------------------------------- Spin-orbit interaction in electron-heavy atom collisions J. E. Sienkiewicz Katedra Fizyki Teoretycznej i Metod Matematycznych Politechnika Gdanska, 80-952 Gdansk, Poland This lecture is devoted to the manifestation of the spin-orbit interaction during electron scattering from heavy spinless atoms. The spin-orbit interaction of the scattered electron in the atomic field is proportional to the scalar product of the electron-orbital-momentum vector and the spin-angular-momentum vector of the electron. This scalar product is positive for electrons with the spin parallel to the orbital momentum and negative for electrons with spins antiparallel to the orbital momentum. The scattering potential consists of the Coulomb and the polarization, and the spin-orbit interaction. Since the last term, namely the spin orbit-interaction, has different signs for spin-up and spin-down electrons one gets different scattering potentials. As a consequence, one gets different scattering cross sections so that one obtains different numbers of spin-up and spin down electrons in the scattering beams. It means that the scattered beam is polarized. Several examples are shown. From chemists point of view it might be interesting that also some studies of spin-dependent electron scattering from oriented molecules have been already performed. ------------------------------------------------------------------------------ The Dirac-Coulomb Sturmian functions: a tool for relativistic atomic physics Radoslaw Szmytkowski Faculty of Applied Physics and Mathematics, Technical University of Gda{nsk, ul. Gabriela Narutowicza 11/12, PL 80--952 Gda{nsk, Poland A purpose of the lecture is to popularize the Dirac--Coulomb Sturmian functions, a powerful tool for relativistic atomic physics introduced recently by Szmytkowski [1]. In the past, there had been at least two attempts to construct the Dirac--Coulomb Sturmians [2 - 4] but it was shown [1] that none of them was successful. In particular, in spite of claims to the contrary [3, 4], the Oxford L-spinors are not the relativistic Sturmians. The Dirac--Coulomb Sturmians generalize the well-known Schr{"odinger--Coulomb Sturmian functions [5] and are non-trivial solutions of a Sturm--Liouville problem consisting of a set of coupled first-order radial Dirac--Coulomb equations augmented by appropriate boundary conditions. Two kinds of the Sturmian functions are found depending on the way in which an eigenvalue parameter is chosen. The Sturmians form discrete functional sets which are complete in the space of two-component spinor functions. The Sturmians of either kind obey two orthogonality and two closure relations. They are ideally suited for constructing a discrete expansion of the Dirac--Coulomb Green function [1]. The Dirac--Coulomb Sturmians may find wide applications in relativistic atomic physics and in QED. For instance, the Sturmian expansion of the Dirac--Coulomb Green function may be used in calculations based on the perturbation theory. This was illustrated by Szmytkowski [1] who derived an analytical formula for a static electric dipole polarizability of the relativistic hydrogen-like atom. The Sturmian functions may be also employed as pseudostates in relativistic electron--atom scattering or photoionization calculations. The relativistic Sturmian functions may be used in finite basis set variational calculations. We shall present results of applications of the Sturmian basis in the variational determination of energy eigenvalues of the Dirac--Coulomb Hamiltonian. It appears that the variational spectrum of the problem has many interesting features, among them it obeys a generalized Hylleraas--Undheim theorem found earlier for the Slater spinor basis by Drake and Goldman [6, 2]. [1] R.Szmytkowski, J.Phys.B 30 (1997) 825--61 [Erratum: 30 (1997) 2747] [2] G.W.F.Drake, S.P.Goldman, Adv.At.Mol.Phys. 25 (1988) 393--416 [3] I.P.Grant, in: ``The Effects of Relativity in Atoms, Molecules, and the Solid State, edited by S. hspace*{15ptWilson, I.P.Grant, B.L.Gyorffy (Plenum, New York, 1991) pp.17--43 [4] I.P.Grant, in: ``Atomic, Molecular, and Optical Physics Handbook, edited by G.W.F.Drake (AIP, hspace*{15ptWoodbury, 1996) pp.258--86 [5] M.Rotenberg, Adv.At.Mol.Phys. 6 (1970) 233--68 [6] G.W.F.Drake, S.P.Goldman, Phys.Rev.A 23 (1981) 2093--8 ------------------------------------------------------------------------------ Ab initio study of SOC effects in molecular spectra and reaction dynamics H.-J. Werner (Stuttgart) ------------------------------------------------------------------------------ ------------------------------------------------------------------------------- POSTERS POSTER 1: Relativistic density-functional theory based on quantum electrodynamics for multielectron systems A. V. Glushkov Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr. ,OHMI, a/c 108, Odessa-9, 270009, Ukraine Within quantum electrodynamics (QED) its developed a density-functional (DF) formalism providing the construction of the optimal one-electron represantation in the theory of the multielectron systems.We use an energy approach based on the adiabatic Gell-Mann and Low formula for the energy shift dE with the QED scattering matrice. It is formulated ab initio criterion for the choice of the atomic core electron density d for atom (molecule) with a few quasiparticles above closed shells core. The optimization criterion for d is reduced to the minimization of the DF which represents the contribution of main polarization diagrams of the QED perturbation theory fourth order: A=direct polarization ,B=exchange (for one-qua- siparticle density system) [1]. These contributions describe collective effects and are dependent on the electromagnetic potential gauge. We have calculated the contributions of A & B diagrams into imaginary part of dE taking into account the exchange of electrons by transverse & longitudinal photons. Minimization of the DF Im dE leads to integro- differential equation for d, solved using the standard numerical code [2]. The developed theory is numerically tested by calculation of the electron structure & spectra for some complex atoms,ions and molecules (Na,Cs,Fr,like ions, N2,O2,CO2,C6H6 etc.) with account of the core polarization [3]. [1] Glushkov A.V. and Ivanov L.N., Phys.Letters A,170,33 (1992). [2] Glushkov A.V. and Ivanov L.N., J.Phys.B, 26,N16, L379(1993). [3] Glushkov A.V. et al, Int.J.Quant.Chem.,(1997). ------------------------------------------------------------------------------------ POSTER 2: SOC effects in spectra of Rydberg resonances for heavy elements in electric field A. V. Glushkov1, S. V. Ambrosov1, T. V. Buyadgi1, and A. V. Efimov2 1 Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine; 2 Institute of Spectroscopy, Russian Academy of Sciences (ISAN), SU-142092, Troitzk, Moscow region, RUSSIA There are presented the results of the theoretical study of the autoionization resonances (AR)in complex multielectron heavy elements systems (heavy rare-earth atoms, their oxides) in the external electric and laser field [1,3]. There have been discovered the unussual especialities of their behaviour in a field, in particular, an effect of giant broadening of the AR widths in the weak external field.There are considered 2 main AR decay channels.One of them is the traditional Beutler-Fano channel.Another one is a new decay type ( the reorientational decay (RD) [2] ).An appreciable dependence of the RD velocity at the moderately weak (sim 100 V/cm) electric field has been predicted [1,3]. The SOC effects role has been found. Detailed information about the AR is needed to optimize excitation and ionization processes.An optimal scheme presumes the compromise between the high excitation probability and high decay rate that determines the lower and upper boundaries for the AR decay rate. The use of the RD channel essentially increases the possibility of such a compromise. New possibilities of the optimization for the laser resonance ionization scheme with account of these effects are indicated (for laser chemistry etc). [1] Glushkov A.V.,Ivanov L.N. Preprint of ISAN N1,2-AS-94; Troitsk, (1994); Proc. 5th ASOSALP Conf.,Paris,1995 [2] Vidolova-Angelova E.P.,Ivanov L.N. J.Phys.B.:At.Mol.Opt. Phys.,24,4147 (1991) [3] Glushkov A.V. et al, Abstr.28th EGAS, Vienna,(1996) ------------------------------------------------------------------------------ POSTER 3: Heavy elements, relativistic-soc effects in catalysis processes A.V.Glushkov, A.F.Kivganov and V.A.Efimov Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine New relativistic theoretical approach has been developed to descibe the catalytic & absorption phenomena with the parti- cipance of the heavy elements. Method is based on the electro- dynamical model and relativistic quantum-mechanical model with the use of the relativistic Dirac equation. It generalizes the early proposed non-relativistic method [1-3]. As an example,we considered the catalytic hydrogen electrooxidation and oxygene electrorestoring reactions and have shown that the correct des- cription of the heavy elements catalytic materials properties requires the adequite account for the relativistic corrections. We also examine an action of the laser and electric field on catalysis process.Some materials non possesing by catalytic properties become the catalisators under action of the laser field & vice versa. Theory of the catalysis in external fields is presented [4]. [1] A.V.Glushkov, Sov.ElectroChemistry. 27,131 (1991). [2] A.V.Glushkov, Sov.ElectroChemistry. 29,358 (1993). [3] A.V.Glushkov, Cat.Lett. to be submitted. [4] A.V.Glushkov, Heavy Elements, Relativistic and Laser Fields Effects in Catalysis, Moscow-Troitzk, 1996. ----------------------------------------------------------------------------- POSTER 4: Relativistic DFT calculations of heavy elements clusters A. V. Glushkov1, Yu. A. Kruglyak1, V. D. Parkhomenko2, P. N. Tcybulev2, A. S.K atashinsky3 1Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine; 2Institute of General and Neorganic Chemistry, NAN Ukraine, Kiev, Ukraine ; 3Kiev Politechnical Institute, Kiev, Ukraine. There are presented the results of calculations for the electron structure, spectra for the lanthanides perovskites (ABO3,A=Ln,Ce; B=Mn,Co), alkali and heavy elements atoms (Nb, Mo) clusters in neutral form & also single-, double-charged ones, on the basis of different calculation methods:density- functional (DF) & relativistic perturbation theory (PT) with pseudopotential zeroth approximation [1].It has been studied the contributions of the correlation and relativistic correc- tions into calculated characteristics, which are to be quite important. This work, in part,supported by the grant of the Ministry of Science and Technology of Ukraine, project N 3.4/382. [1] A.V.Glushkov, E.P.Ivanova, J.Quant.Spectr.Rad.Transfer,36, 127 (1986). [2] A.V.Glushkov, Int.J.Quant.Chem.(1997),to be submitted. --------------------------------------------------------------------------- POSTER 5: Spin-orbit effects in electron satellites spectra production in intense laser field on nuclei in atom, ion and molecule: relativistic and QED approaches A. V. Glushkov12, S. V. Malinovskaya3, I. Shpinareva1, S. Dankov1 1 Dept .Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine; 2 Institute of Spectroscopy, Russian Academy of Sciences (ISAN), SU-142092, Troitzk, Moscow region, RUSSIA; 3 Odessa Center of Spectroscopy, a/c 108, Odessa-9,270009 The paper deals with a group of the laser field effects on nuclei in the neutral atoms,ions & molecules with production of the electron satellites set in spectra and goes on our work within the following directions in a laser- electron- nuclear spectroscopy:1).the mixed Y-optical quantum transitions under intense laser field;2).manifestation ofthe nuclear properties in the optical spectra and the use of this effect in nuclear investigations with application of lasers; 3). a drivening by the charged particles beams papameters by means the laser radiation effect on the electron shell surrounding the nuclei. Theoretical results of the calculation of the electron-nuc- lear Y-transition spectra (set of electron satellites) of the nucleus in a multicharged atomic ion & neutral atom in presence of the intense field are presented. A mechanism of formation of the satellites in a case of the ion (rigid electron shell) involves the direct interaction between Y quantum and atomic electrons.For atom & molecule (loose shell) the "shaking" of shell resulting from the interaction between the nucleus & Y- quantum is predominant [1,2]. The relative intensities of the satellites are calculated within the relativistic version of the energy approach (S-matrix Gell-Mann and Low formalism) [2]. The possible satellite observation experiment is in detailes discussed to provide a search of optimal experiment conditions. [1] Ivanov L.N. and Letochov V.S. Sov.JETP, 93,396,1987. [2] Glushkov A.V.et al, Abstr.28th EGAS,Vienna,(1996). [3] Glushkov A.V. and Ivanov L.N. Phys.Lett.A,70,33,1992; Preprint of ISAN N1-AS-93, Moscow,1993. --------------------------------------------------------------------------------- POSTER 6: Ground and excited states of alkali dimers: potential curves with spin-orbit coupling A.V.Glushkov1, S.V.Malinovskaya2, L.A.Vitovetskaya1 1 Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine; 2Center of Spectroscopy, a/c 108, Odessa-9,270009 Within formally exact perturbation theory with model zero approximation [1-3], it has been carried out the calculation of the potential curves for the ground and excited states of the homo- and heteronuclear alkali dimers AB (A,B = K,Cs,Fr) with account of the relativistic effects [3].A semiempirical model of the Cohen-Schneider type [4], based on the exactly calculated atomic splittings [5,6] is given for treatment of spin-orbit coupling effects. There have been predicted some unusual especialitites in the spectra of the excited states of the heavy alkali diatomics [7]. A part of the results are obtained at first. [1] Glushkov A.V. Sov.J.Phys.Chem. 65,N9 (1991); 66,N10 (1992); Sov. J. Struct. Chem. 34, N5 (1993) [2] Glushkov A.V. and Ivanov L.N. Phys.Lett.A 70, N1 (1992) [3] Glushkov A.V. Int.J.Quant.Chem., to be published. [4] Cohen J.S. and Schneider B. J.Chem.Phys.61,N8 (1974) [5] Glushkov A.V. Sov.Opticks and Spectroscopy 36,N6 (1994) [6] Glushkov A.V. Sov.Applied Spectr.Journ.36,N6 (1994); [7] Glushkov A.V. Phys.Lett.A , to be published. ------------------------------------------------------------------------- POSTER 7 Collision-induced singlet-triplet transitions in molecular oxygen G. I. Kobzev1 and B. F. Minaev 2 1Department of Chemistry, Karaganda University, Universitetskaja 28, 470074 Karaganda, Kazakhstan; 2Department of Chemistry, Cherkassy State University, Cherkassy, Ukraine Different types of collision complexes between O_2 and diamagnetic species (H_2, NH_3, ethylene, benzene) have been considered by MINDO/3 CI, MRCI and MCSCF response (6-31 G*) calculations in order to simulate paramagnetic spin-catalysis of photophysical and photochemical properties of oxygen containing organic solvents and mixtures of gases. ------------------------------------------------------------------------- POSTER 8: Quadratically convergent multiconfiguration Dirac-Fock and multireference relativistic configuration interaction calculations for many-electron systems Marius J. Vilkas1, Yasuyuki Ishikawa1 and Konrad Koc2 1Department of Chemistry and The Chemical Physics Program, University of Puerto Rico, P.O.Box 23346, San Juan, PR 00931-3346, USA; 2Department of Physics, Pedagogical University, ul. Podchorazych 2, 30-084, Krakow, Poland A quadratically convergent Newton-Raphson algorithm for relativistic multiconfiguration Dirac-Fock self-consistent field calculations is developed and implemented with analytic basis sets of Gaussian spinors. A procedure to perform second-order energy optimization for a general class of multiconfiguration wave functions constructed from one-particle Dirac spinors is described. We report the results of relativistic multiconfiguration Dirac-Fock self-consistent field calculations and relativistic multireference configuration interaction calculations based on the multiconfiguration Dirac-Fock wave functions for the lowest 3P_0, % 3P_1, and 3P_2 states of oxygenlike iron (Fe+18) and ground-state beryllium and berylliumlike neon (Ne+6), species which exhibit the near degeneracy characteristic of a manifold of strongly interacting configurations. ---------------------------------------------------------------------------- POSTER 9: Double perturbation approach to the relativistic hydrogenic atom in a magnetic field R Kozlowski and A Rutkowski Institute of Mathematics and Physics, Pedagogical University, ul. Zolnierska 14, 10-561 Olsztyn, Poland. Double perturbation theory is developed for the case where relativity is one perturbation and the second perturbation describes the interaction with external magnetic field. Relativity is treated according to direct relativistic perturbation theory developed by Rutkowski [J. Phys. B 19, 149, 3431, 3443 (1986)] and Kutzelnigg [Z. Phys. D. 11, 15, (1989); 15, 27 (1990)]. The relevant radial perturbation equations and formulae for the corrections for the energy are derived. For the ground state up to the first order in magnetic field all the differential equations arising are solved directly to infinite order in relativity. The general solutions of the radial equations are obtained by expansion in appropriate Laguerre polynomials. Exact energy corrections for zeroth and first order as well as very accurate results for second and third order in relativity are presented up to twelve order in magnetic field. ------------------------------------------------------------------------------ POSTER 10: Relativistic effects in Ba D.Kulaga, J. Migdalek Pedagogical University in Cracow, ul. Podchorazych 2, 30-08 Krakow In order to systematically study the influence of relativistic effects on energy levels and oscillator strengths in Barium, we used four diffrent approaches. First we performed calculations using ab-initio non-relativistic Hartree-Fock (HF) and a pseudorelativistic method (HFR) in which mass-velocity and Darwin contributions were included to evaluate the one-electron and the total binding energy. In the second part of calculations we used a semiempirical fit of Slater intengrals to minimize discrepancies between observed and computed energy and core polarisation corrections to the dipole transition matrix element (HF+CP+FIT and HFR+CP+FIT, respectively). To account for intravalence electron correlation, CI approach has been used. The basis set for the calculations consist of 13 even and 7 odd configurations. Computations are performed in LS copupling scheme. As a tool has computer package written by R.D.Cowan of Los Alamos National Laboratory has been used. The calculated energy levels and the oscillator strengths between levels under considerations have been compared with available data. ----------------------------------------------------------------------------- POSTER 11: Relativistic calculation of Ne-and Ar-like multicharged ions: SOC effects S. V. Malinovskaya1, V. N. Polischuk2 and V. N. Orlova2 1Odessa Center of Spectroscopy, a/c 108, Odessa-9,270009; 2Dept. Appl. Math. and Lab. At. -Nucl. -Mol. Spectr., OHMI, a/c 108, Odessa-9, 270009, Ukraine Laborotary X-ray investigations supplemented recently with new ideas concerning resonant photoionization as the pumping mecha- nism.Its known that the spectral intensity of a pump line would be more than 10(10)w/cm(2)mA.In this case the presence of strong electric microfields complicates a prediction of spectroscopic characteristics for ions. As result a comprehensive theoretical model to describe laser enhancement in plasma ist elaborated yet. Ne - like scheme for lasing represented to be one of the promising scheme. In this light the precise calculations of the energies and transition probabilities,excitation cross-sections of a great impotance. We present the results of the theoretical and experimental studing the spectra (wavelengths) , transition probabilities of 3-3, 3-4 electron and 2-2 vacancy transitions for Ne-like isoelectronic sequence (19>> please send a preprint of papers funded by REHE to Bernd A. 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