The electronic structure of the dizincocene core

Ab initio plane wave based density functional theory calculations were used to examine the properties of the dimetal core of the recently synthesised dizincocene Zn2(η5-C5Me5)2. Neutral Zn2 and the zincous dication Zn22+ were the primary targets and copper dimer Cu2, iron dimer Fe2 and the simpler model dizincocene Zn2(η5-C5H5)2 were examined for comparisons. The zincous ion has features arising from mixing of s-, p-, and d-functions that appear in the isoelectronic copper Cu2 (S = 0) dimer, iron Fe2 (S = 0) dimer and the dizincocene molecule. Isometric surfaces of the total charge, Kohn-Sham level partial charge density and the electron localization function (ELF) are reported. The metal-metal valence basin of the ELF density comprised toroidal and axial components, a motif common to the copper and iron dimers and dizincocene. These results are important for understanding the structure of the known and hypothetical dimetallocenes of the first transition series.