Calculations of overlap integrals over Slater type orbitals using recurrence relations for expansion coefficients

Using formulas for the expansion of overlap integrals with the same screening constants in terms of Slater type orbitals (STOs), sets of recurrence relations are established for the expansion coefficients. These recurrence relations are especially useful in the calculation of overlap integrals for large quantum numbers, which occur in the series expansion formulas for multicenter multielectron integrals of integer- and noninteger-n STOs. An accuracy of the computer results is satisfactory for arbitrary quantum numbers, screening constants and location of atomic orbitals.