***************************************************************
**** ****
**** ESF Programme ****
**** ****
**** RELATIVISTIC EFFECTS IN HEAVY ELEMENT CHEMISTRY ****
**** AND PHYSICS ****
**** ****
***************************************************************
Newsletter No. 9 (17 October 1994)
______________________________________________________________
Editor: Bernd Hess, hess@rs9.thch.uni-bonn.de
Tel. 49-228-732920
FAX 49-228-732251
______________________________________________________________
The programme 'Relativistic Effects in Heavy-Element Chemistry and Physics'
('REHE') has been initiated by the European Science
Foundation in November 1992 and it is expected to run for 5 years, i.e.
from 1993 through 1997. The programme is intended to strengthen the in-
dicated "field" and to facilitate interactions between European scientists
concerned with related topics.
The 'Steering Committee' of the programme has at present the following
members:
E. J. Baerends (Amsterdam)
J.P. Desclaux (Grenoble)
K. Faegri (Oslo)
I.P. Grant (Oxford)
B. Hess (Bonn, Vice-Chairman)
H. U. Karow (ESF)
J. Karwowski (Torun)
P. Pyykko (Helsinki, Chairman)
K. Schwarz (Vienna)
A. Sgamellotti (Perugia).
================================================================================
--- E D I T O R I A L
Please send material for the forthcoming newsletter to my attention,
hess@rs9.thch.uni-bonn.de
The newsletter will be sent out every second month around the 10th day
of the month. Contributions should arrive in Bonn until the end of the
preceding month.
The next newsletter (#10) is scheduled for Beginning of December 1994.
Please send your contributions until end of November 1994.
Please send material >by e/mail< that enables us to fill the
following topics in forthcoming newsletters
================================================================================
--- E S F B A C K G R O U N D
The European Science Foundation was established in 1974. Its Member
Organizations are the major European academies, research councils and
other institutions supporting scientific research nationally. Although
these are funded mainly by governments, the ESF itself is a
non-governmental organization. It maintains close associations with other
international bodies with interests in scientific research, particularly
the Commission of the European Communities and the Academia Europaea.
How ESF works
ESF pays for its activities through the contributions of its Member
Organizations. Contributions are made both to the ESF basic budgets, to
which member organizations contribute on a scale that is calculated on
the basis of national incomes, and to specific programmes and projects
in which certain Member Organizations may have particular interest.
The modes of ESF scientific work vary with the expressed needs, and may
change in character over the years. Broadly, ESF Scientific Programmes
almost always contain teams of scientists who carry out research. ESF
Scientific Networks discuss, plan, innovate, analyse or co-ordinate
research, but seldom carry out large amounts of substantive research.
Programmes are often long-term, and are funded (except in the development
phase) by participating Member Organizations. Networks are usually of
shorter term (three years); they are funded from the Network Account
within the ESF basic budget.
ESF also organizes, jointly with the Commission of the European
Communities, a programme of European Research Conferences.
================================================================================
--- F E L L O W S H I P S
In the framework of the REHE programme, there is support available
for visits of doctoral students and also for senior scientists at
institutions in a foreign partner country. This support covers visits
lasting 2-4 months ("long-term visits") which will give the holders
time to acclimatize to the methods used in the host laboratory as well as
short visits ("short-term visits") of only a few days.
Please send a short application detailing the project, the names of the
scientists involved and the aproximate date and duration of the visit
to either Pekka Pyykko or Bernd Hess. Please refer to REHE newsletter #7
for details.
>>> Should the planned dates of your stay change for any reason, you are
>>> requested to notify the Chairman as soon as possible with a copy to
>>> the ESF.
================================================================================
--- 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 I. Martin]
REPORT ON THE VISIT BY INMACULADA MARTIN TO PROFESSORS
KARWOWSKI AND DIERCKSEN ON REHE GRANT No. 10.
Place: Max-Planck-Institut fuer Astrophysik; Garching bei Muenchen,
Germany
Dates: 1-31 August 1994
Subject: A universal pattern of the QDO oscillator strengths in atoms.
Atomic oscillator strengths calculated with the quantum defect
orbital (QDO) method depend upon a certain combination of the quantum
numbers, degree of ionization of the atom, and the energies of the two
states involved. However, the f-values are independent of the number of
electrons and the nuclear charge. If the degree of ionization and the
quantum numbers are fixed, then the QDO oscillator strength is just a
function of the state energies and is independent of the specific atom.
As a result of this study, the QDO f-values have been expressed as
universal functions of the state energies in both relativistic and non-
relativistic formulations of the theory. The results, in addition to
their practical usefulness (they allow for an immediate estimation of
oscillator strengths) permit a deeper understanding of the relations
between direct and indirect relativistic effects in the QDO approach.
----------------------------------------------------------------------
OUR MOST RECENT PUBLICATIONS ON RELATIVISTIC CALCULATIONS
-"Relativistic quantum defect calculations on the Cu isoelectronic
sequence"
C. Lavin, C. Barrientos, I. Martin
International Journal of Quantum Chemistry 50 (1994), 411.
-"Core polarization effects in the relativistic quantum defect orbital
theory"
D. Bielinska-Waz, I. Martin, J. Karwowski
Acta Physica Polonica 85 (1994), 805.
-"Triplet-triplet transitions in zinc-like ions"
P. Martin, C. Lavin, I. Martin
Z Physik D: Atoms, Molecules and Clusters 30 (1994), 279.
-"Relativistic quantum defect orbital calculations on triplet-triplet
transitions in cadmium-like ions"
C. Lavin, I. Martin
Journal of Quantitative Spectroscopy and Radiative Transfer 52 (1994), 21.
-"Measurements and calculations of the oscillator strength spectral
density of Cd"
M. Amad, U. Griessman, I. Martin, A.M. Baig
Journal of Physics B: Atomic, Molecular and Optical Physics, to appear
(1994).
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[communicated by P. Marketos]
Dr. Fumihiro Koike, of School of Medicine,
Kitasato University, Japan, visited the Foundation
for Reasearch and Technology (FORTH) offices
in Athens, and discussed with Dr Pan Marketos
large scale MCDF-CI calculations for 2p ---> 3d
excitations in elements of the first transition
series. Professor Ian Grant is also involved in the theoretical part
of this project. Calculations are performed using the GRASP code.
Experimental groups in Japan are also involved.
Results for Mn are satisfactory. For this atom, the spectrum
in the 2p-absorption region measured by photoion yield
method agrees quite well with the convoluted curve
in which a Lorentzian natural profile and a triangular
apparatus function are applied for each oscillator strength.
In another project involving GRASP, the structure of high lying levels
of the type 2p^5 4f in NaII, 2p^4 5g in NaIII and 2p^3 6h in NaIV has been
investigated. Beam-foil spectroscopic studies as well as excitation function
studies on these ions have been carried out at the Tata Institute
of Fundamental Research, Bombay. Experimentally
determined lifetimes for these levels
agree quite well with theoretical calculations
performed in collaboration with Dr Pan Marketos
(FORTH, Athens). As a result, tentative assignments for the
levels involved in experimentally determined
transitions have also been provided. The calculation
showed that the nf, ng and nh orbitals used for the
description of the ionic levels may be treated
as hydrogen-like.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[communicated by M. Barysz]
Report on results obtained by Maria Barysz during a
three-month fellowship granted within the REHE project.
Author: Maria Barysz
Host: Geerd H. F. Diercksen
Place: Max-Planck-Institut fur Astrophysik, Garching bei Munchen
Time: 20.06.94 - 20.09.94
Subject:
Developing methods for simultaneous inclusion of electron
correlation and relativistic effects in theory of molecular structure.
DESCRIPTION OF THE PROJECT AND RESULTS
Motivation.
Importance of relativistic effects in describing properties of
atoms and molecules has been recognized long ago. Some
phenomena, as for example spin-forbidden electronic transitions
or fine-structure splittings, cannot be described at
all without taking into account relativistic effects. Many other
properties are considerably dependent on the relativistic effects.
Relativistic effects appear to be important also in systems
containing light elements only. Particularly in these cases the
theoretical description may be very accurate on the
non-relativistic level and therefore including relativistic
effects becomes an imperative if a good agreement with
experiment is to be expected. During last several years a
general multi-reference non-relativistic direct CI programme
based on the symmetric group approach (SGA) to theory of
many-electron systems has been developed in Garching.
It allows for accurate, non-relativistic, treatment of small
molecules. Therefore, at this stage of development of the code,
the low-order relativistic effects have to be included.
Method.
SGA has also been applied to construct CI algorithms in the
case of spin dependent Hamiltonians. However, then the
degree of complication of the method is much higher. Instead of
the representation matrices of the permutation group which are
easy to obtain from many algorithms, matrices that depend upon
the form of the spin-dependent part of the Hamiltonian appear in
the matrix element expressions. The formalism, in its general
form, has been developed and detailed formulae have recently been
derived. As a result, general expressions for matrix elements of
spin-dependent operators in a basis of non-relativistic
configurations have been obtained. This allowed for a
formulation and coding of a configuration interaction method
based on the Pauli approximation. This kind of approach proved
to be very successfull in the case of atoms. It is anticipated
that also in the case of molecules containing atoms with low and
medium nuclear charges the method should be applicable. It is
much simpler than the ones based on the full (four-component)
relativistic treatment. The CI method using an explicit
projection onto the positive-energy subspace (the no-pair
approach) is being implemented now. It will further extend
applicability of the method. An immediate goal of this project
is to implement a spin-dependent CI method in both standard
Pauli and in the no-pair modes.
Scientific goals.
Studies on the electric and magnetic properties of
molecules in the spin dependent formalism, studies on
spin-forbidden transitions, investigation of the influence of
the spin-orbit coupling on structure of the energy
hypersurfaces, just to mention the most important directions of
the studies.
The main objective of the present project is to extend the
nonrelativistic symmetric-group-approach-based CI (SGA-CI)
programme to include relativistic effects within scalar
approximations. The nonrelativistic SGA CI
code has been developed in Garching as a result of
cooperation between G. H. F. Diercksen, W. Duch, and J.
Karwowski [1]. The one-electron Breit-Pauli relativistic
corrections have been
very recently added to this code by N. Flocke and M. Barysz
in cooperation with G. H. F. Diercksen and J. Karwowski.
During the last three months Maria Barysz has been
working on two problems:
I. Calculation of the two-electron Breit-Pauli
relativistic corrections.
The following two-electron corrections
have been programmed:
Two-electron spin-other-orbit interaction.
Two-electron spin-spin interaction and Fermi
contact interaction
Two-electron orbit-orbit interaction.
Two-electron Darwin correction.
All integrals appearing in these corrections have been
expressed as combinations of the
overlap integrals and the electron-repulsion integrals.
In effect, rather complicated expressions for the relativistic
corrections may be handled in a simple way using subroutines
for calculating the ``elementary'' integrals. These
subroutines have been developed and optimized
earlier in order to handle the nonrelativistic case. During the
past three months all algorithms have been derived and most
of them have been programmed.
However, the relativistic CI code is rather far away from the
stage in which it might be used in routine calculations. Now,
testing correctness the code is the main problem.
II. It has been recognized that including the no-pair approach [2],
i.e. projection of the Hamiltonian onto the
positive-energy subspace,
essentially extends applicability of the programme. Therefore
works aimed at an implementation of this approach within the SGA
formalism have been undertaken. The algorithm for the algebraic
approximation to the no-pair approach have been worked-out and, in a
major part, implemented. However, similarly as in the case of the
Breit-Pauli approximation, testing correctness of the code has not
been performed yet. Several
testing algorithms are being currently developed.
References:
[1] W. Duch and J. Karwowski, Comuter Phys. Rep. 2(1985)93;
Theoret. Chim. Acta 71(1987)187; G. H. F. Diercksen, W. Duch and
J. Karwowski, Phys. Rev. A41(1990)3503.
[2] J. Sucher, Phys. Rev. A22(1980)348; J. Alml\"of, K. Faegri
and H. H. Grelland, Chem. Phys. Letters 114(1985)53; B. A. Hess,
R. J. Buenker and P. Chandra, Int. J. Quantum Chem. 29(1986)737;
R. Samzow, B. A. Hess and G. Jansen, J. Chem. Phys. 96(1992)1227.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[communicated by Stefan Keller]
Status report of the relativistic (e,2e) project pursued
by the Cambridge/Frankfurt/Belfast collaboration
As was indicated in an earlier REHE newsletter, groups from Cambrigde
(Whelan, Ast), Belfast (Walters) and Frankfurt (Keller, Dreizler) have been
engaged in setting up a relativistic DWBA code to describe electron impact
ionization of the innermost electrons of heavy metallic target atoms
by a consistent first order calculation within Furry picture QED.
While earlier theories have shown a pronounced tendency towards overestimating
the absolute experimental results of Nakel and collaborators (Tuebingen),
first results using our approach agree quite well with the experiment (PR A50,
R1, PR A 50, in press).
During visits of Stefan Keller to Cambridge and Belfast earlier this year,
funded by the ESF through the REHE program, we have therefore
started a comprehensive study of different target systems and kinematical
conditions which is still under way due to the large amounts of CPU time
needed. Furthermore, we have investigated the reasons for the failure of
previous approximate first order theories. Over the summer, we have extended
our work to include a spin polarized incident channel. Here a first experiment
has been carried out by the Tuebingen group, but a number of conceptual prob-
lems involving the definition of spin polarized relativistic electronic states
in the presence of external fields has to be addressed in order to arrive at
a sensitive theoretical description of the data.
We expect that by systematically extending our method while maintaining a close
collaboration with the experimentalists, the understanding of the basic ioniza-
tion process of inner shells of heavy atoms will be further improved.
S. Keller would like to thank the ESF for the continuous support of his work
on this project. He also gratefully acknowledges the hospitality of the
Cambridge and Belfast groups.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[communicated by J. Sienkiewicz]
Report on the ESF scholarship of J. E. Sienkiewicz at University of
Oxford
Within the REHE fellowship program, I spent three months (9 July - 8
October 1994) with Prof. I. P. Grant in the Mathematical Institute at
University of Oxford. We collaborated on the relativistic
multi-configurational method in the elastic low-energy scattering of
electrons from atoms.
During my stay in Oxford, I calculated the 'final' (including continuum
orbital) and 'initial' (bound) multi-configuration states of the
electron-xenon system. The 'initial' state accounts for correlation effects
between the scattered electron and bound electrons from the target atom.
First, I used the computer code GRASP2, developed in Oxford, to
generate the relativistic ns, np and nd orbitals up to n = 12. Next, I
made a CI calculation of the ground state of Xe and used these atomic
orbitals for the CI calculation of the negative ion of Xe. I made an
attempt to incorporate SCF orbitals of the negative ion in my scattering
state, but it required too much time and after discussion with Prof.
Grant I decided to work on it after my return to Gda\'nsk. I also
developed further my own computer code by including new subroutines
governing the SCF iteration process, calculating the relativistic
phase shifts and solving the system of linear equations needed to
calculate an eigenvector of the scattering multi-configurational
state. Finally, using the RATR code of S. Fritzsche I obtained a
converged solution of the continuum Dirac spinor. At the end of my
stay, I wrote a theoretical chapter for an article which we shall publish.
I am very grateful to ESF for providing funds for this project and I
thank Prof. Ian P. Grant for the help and discussions during my stay in
Oxford. I also thank Dr. Stephan Fritzsche for the assistance in
customizing his computer code.
J\'ozef E. Sienkiewicz
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
================================================================================
--- 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 H. Schmidbaur]
Preliminary Announcement
For 1995 Professor Notger Roesch and myself are planning to have a
Symposium on Experimental and Theoretical Chemistry of Gold.
Such a meeting will of course be of great interest to many colleagues
engaged in research in the broad area of relativistic effects in the
chemistry and physics of the heavy elements in general, and of gold
in particular. The meeting will be held in the Munich area, readily
accessible by air, rail, and road. It appears that September 1994
should be considered as a suitable period, and in a brief discussion
with Professor Pyykkoe the days from September 8-13 were found to be
most likely the best choice. We are thinking of a three-to-four day
event, with experimentalists and theoretical groups well balanced in the
program. A one-day week-end break should give a chance for recreation
and personal contacts.
As judged from the published research activities, a group of at least
60-80 people can be expected to participate from all over the world.
We hope to be able to attract outside funding, but we will also have to
rely on standard registration fees.
I put this preliminary announcement into the REHE newsletter in the hope
that all its readers are giving this proposal some thought and perhaps
let me know if they are considering to participate. A more detailed
leaflet will be available by December 1994.
Thank you for your interest:
Hubert Schmidbaur, TU Muenchen.
================================================================================
--- P O S I T I O N S available
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
OXFORD UNIVERSITY MATHEMATICAL INSTITUTE
Postdoctoral Research Assistant in Mathematical Physics
An EPSRC-funded Postdoctoral Research Assistantship is available to
work on the relativistic R-matrix method for studying electron
scattering from atoms and ions and photo-excitation/ionisation
processes in heavy elements. The project will involve some theory as
well as extension and optimization of existing code to run on
supercomputers. Appointment will be on the academic-related research
staff Scale 1A (salary \pounds 13,941 -- \pounds 18,486 per annum for
a period of up to two years starting 1 January 1995, or as soon as
possible afterwards.
Applications are invited from those with an interest in applying
relativistic quantum theory to atomic and molecular physics, or related
fields, and having suitable computational experience.
Applicants should send a curriculum vitae, including the names of two
referees, to Professor I.\ P.\ Grant FRS, Mathematical Institute,
24-29 St.\ Giles', Oxford, OX1 3LB (Tel: +44 (0)865 273538/273551,
Fax: +44 (0)865 273583, email: ipg@maths.ox.ac.uk) from whom further
information can be obtained.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
================================================================================
--- P O S I T I O N S sought
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[no material for this section in the current newsletter]
================================================================================
--- G O S S I P
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[no material for this section in the current newsletter]
================================================================================
--- ADDRESS LIST
The REHE address list comprises 127 scientists as of October 17, 1994; the
current list will be provided with newsletter no. 10
In order to join the REHE mailing list, please complete the form below
and send it back per e-mail to hess@rs9.thch.uni-bonn.de
>>> PLEASE include TEL, FAX, E-MAIL <<<
=================================================================
I am interested in receiving the REHE newsletter
NAME
-----------------------------------------------------------------
ADDRESS
-----------------------------------------------------------------
-----------------------------------------------------------------
TEL
-----------------------------------------------------------------
FAX
-----------------------------------------------------------------
E-MAIL
-----------------------------------------------------------------
MAIN RESEARCH INTERESTS
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
End of REHE Newsletter No. 9