Structural and photoelectron spectroscopic study on the heterotrinuclear nickel–titanium dioxide carbonyl complexes Ni2TiO2(CO)n− (n = 2–4)

Abstract

Herein, the configurations and intrinsic electronic properties of heteronuclear transition metal dioxide carbonyl anions Ni₂TiO₂(CO)_n⁻ (n = 2–4) in the gas phase were investigated using mass spectrometry coupled anionic photoelectron spectroscopy, ab initio calculations, and simulated density-of-state (DOS) spectra. The results clearly show that the binding of electrons is enhanced by the addition of CO. The ground state structures of Ni₂TiO₂(CO)_n⁻ (n = 2–4) are characterized to show that three transition metal atoms (one Ti atom and two Ni atoms) forming a quasi-line is favored. The interaction between Ni and C becomes weaker as the cluster size increases. The natural electron configuration shows that the extra electron is enriched on O atoms attached to Ti, and there is strong interaction between Ti and O atoms. This work gives significant insight into the configuration and electronic structures of nickel-titanium dioxide carbonyl anions, which has potential application in adsorption of carbon monoxide on the surfaces/interfaces of alloys.