Mulliken atomic partial charges

Definition:

Z_A - atomic nuclear charge

P_kl - atomic population matrix elements

Reference:

1. R. S. Mulliken, J. Chem. Phys.,1955 23, 1833-1840.
2. I. G. Csizmadia, Theory and Practice of MO Calculations on Organic Molecules, Elsevier, Amsterdam, 1976.