  General method is suggested to find non-relativistic and relativistic matrix
elements of one- and two-electron operators for any number of open shells in
atom, requiring neither coefficients of fractional parentage nor unit tensors.
It is based on second quantization in coupled tensorial form, angular momentum
theory in orbital, spin and quasispin spaces and generalized graphical
technique. All matrix elements (diagonal and non-diagonal with respect to
configurations) differ then only by projections of quasispin of separate shells
and are expressed via completely reduced (in three spaces) matrix elements of
second quantization operator and its products. Thus, all matrix elements are
treated uniformly. This approach allows one to generate fairly accurate
databases of atomic parameters.
