To gain a beYer reference point, NPA charges were also calculated for 1a-c along with some analogues of 2a-c in which the Zn atoms are replaced by H or Li atoms. The aluminium, gallium, and silicon dihydrides compounds are known, of which the aluminium analogue can be formed from oxidaOve addiOon of H2 to 1a. The dilithium analogues of 2a-c are enOrely theoreOcal. This series was explored to understand the effect of changing electronegaOvity on bond polarisaOon. Comparison