Correlated molecular and cumulative atomic multipole moments

Molecular charge distributions for several neutral and charged molecules (LiH, HF, H2O, NH3, CH3, CH4, OH−, H3O+, N2, CO, HCN, H2CO, C2H2, and N2O) have been decomposed into the sets of correlated cumulative atomic multipole moments (CCAMM). These segmental moments sum up to the corresponding correlated molecular multipole moments (CMMM) and match closely the available experimental values. The corresponding correlation contributions have been compared with basis set extension effects for a number of 6-311G(nd/mp) basis sets with multiple polarization functions. The uncorrelated moments have been presented too, allowing the correction of intramolecular correlation and basis set truncation effects in the electrostatic multipole interaction energies, molecular electrostatic potentials, etc.