Ground states of molecules. 53. MNDO calculations for molecules containing chlorine

MNDO calculations of heats of formation, dipole moments, ionization potentials, and structures are reported for a wide range of compounds containing chlorine in its characteristic valence state (Cl I ) and one or more of the elements H, B, Be, C, N, O, and F. The calculated errors in the heats of formation and the dipole moments are not significantly greater than those previously reported for compounds containing no chlorine. First vertical ionization potentials were on average 0.95 eV too high. The ordering of higher cationic states was found to be correct, even for species such as Cl 2 O, Cl 2 , and HOCl, where ab initio –Koopmans' theorem calculations predict the incorrect ordering. The calculated energies and geometries of compounds such as CIF 3 are qualitatively incorrect, probably because of the lack of 3 d atomic orbitals in the orbital basis set.