Аннотация:
An algorithm for the variational calculation of atomic D states employing n-electron explicitly correlated
Gaussians is developed and implemented. The algorithm includes formulas for the first derivatives
of the Hamiltonian and overlap matrix elements determined with respect to the Gaussian nonlinear
exponential parameters. The derivatives are used to form the energy gradient which is employed
in the variational energy minimization. The algorithm is tested in the calculations of the two lowest D
states of the lithium and beryllium atoms. For the lowest D state of Li the present result is lower than
the best previously reported result