Correlation of core electron binding energies with charge distributions for compounds of carbon, silicon, and germanium

Core electron binding energies for analogous compounds of carbon, silicon, and germanium have been measured by X-ray photoelectron spectroscopy in the gas phase. The chemical shifts have been correlated by the electrostatic potential equation using charge distributions from extended Huckel theory, CNDO/2, and an electronegativity equalization method. The data can be rationalized without any consideration p..pi -->..d..pi.. or p(pi)..-->..d(pi) in the silicon and germanium compounds.