About us


Petersburg Nuclear Physics Institute

Advanced development division

Quantum Physics and Chemistry Department

The main direction of our work is development of electronic structure calculation methods for molecules containing heavy elements. The aim is to elaborate technique and programs which allow one to perform very accurate calculations providing smallest computational expenses. It can be reached with the help of "two-step" methods which enable to "split" the correlation structure calculation of such molecules on two consequent calculations in valence and core regions.

This activity was initiated by the experimental study of the Parity Non-Conservation (PNC) effects in such molecules as TlF and YbF and started in 1982 with PhD work of A.Titov. Thesis " Effective Potentials and Generalized Brillouin Theorem for electronic states of molecules" was defended in 1986. In 1996, PhD thesis "Development of Relativistic Effective Core Potential method" ( .dvi file - in Russian. Brief review of the thesis .dvi file - in Russian.) was defended by N.S. Mosyagin where topics related to generation of the Generalized Relativistic Effective Core Potentials (GRECPs) and RECPs for transition and rare-earth elements were considered.

Now we are working in the following directions:

  • theory and generation of RECPs for high precision calculations;
  • non-variational and variational electronic structure restoration in core regions of heavy atoms-in-a-molecule after the ECP calculation;
  • molecular calculations and incorporation of the GRECP technique into packages for correlation structure calculations such as MOLCAS, MRD-CI (Multi-Reference Configuration Interaction with single and Double excitations, RCC (Relativistic Coupled-Cluster) and CI/MBPT;
  • calculation of matrix elements of operators (hyperfine structure, parity non-conservation effects etc.) which are singular close to heavy nuclei,
  • variational principles, spin-orbit interaction, unitary group, embedding potential, etc.
  • the EXP-T program system for relativistic multireference coupled cluster calculations

For details see our recent publications and preprint.
Also, take a look on our scientific cooperation and grants.

The computer codes developed by our lab are available by e-mail request.

If you are interested in knowing more about our work, current projects or you want to make some comments, do not hesitate to contact us. We are looking for motivated and talanted undergraduate and graduate students to work in our lab over diploma or theses

Twenty years of Quantum Chemistry Laboratory site