Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generalized Relativistic Effective Core Potential Method: Theory and
  calculations   In calculations of heavy-atom molecules with the shape-consistent
Relativistic Effective Core Potential (RECP), only valence and some outer-core
shells are treated explicitly, the shapes of spinors are smoothed in the atomic
core regions and the small components of four-component spinors are excluded
from calculations. Therefore, the computational efforts can be dramatically
reduced.
  However, in the framework of the standard nodeless radially local RECP
versions, any attempt to extend the space of explicitly treated electrons more
than some limit does not improve the accuracy of the calculations. The errors
caused by these (nodeless) RECPs can range up to 2000 $cm^{-1}$ and more for
the dissociation and transition energies even for lowest-lying excitations that
can be unsatisfactory for many applications. Moreover, the direct calculation
of such properties as electronic densities near heavy nuclei, hyperfine
structure, and matrix elements of other operators singular on heavy nuclei is
impossible as a result of the smoothing of the orbitals in the core regions.
  In the present paper, ways to overcome these disadvantages of the RECP method
are discussed. The developments of the RECP method suggested by the authors are
studied in many precise calculations of atoms and of the TlH, HgH molecules.
The technique of nonvariational restoration of electronic structure in cores of
heavy atoms in molecules is applied to calculation of the P,T-odd
spin-rotational Hamiltonian parameters including the weak interaction terms
which break the symmetry over the space inversion (P) and time-reversal
invariance (T) in the PbF, HgF, BaF, and YbF molecules.

25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph