Spin-dependent operators in correlated Gaussian bases

In their textbook, Suzuki and Varga [(Springer, Berlin, 1998)] present the stochastic variational method with the correlated Gaussian basis in a very exhaustive way. The matrix elements for central potentials are expressed in an elegant form, but the elements for spin-dependent operators, when treated, are given as very cumbersome expressions. We find many formulas for those elements. Their expressions are given in terms of the same geometrical...