An investigation of the bonding in [Ru2(O2CCF3)4] and [Ru2(O2CCF3)4(NO)2]

Abstract

Vapour-phase He I and He II photoelectron (p.e.) spectra have been obtained for [Ru₂(O₂CCF₃)₄] and [Ru₂(O₂CCF₃)₄(NO)₂]. Extended-Hückel and Fenske–Hall calculations of the model systems [Ru₂(O₂CH)₄] and [Ru₂(O₂CH)₄(NO)₂] were used to analyse the bonding in these complexes and to interpret the p.e. spectra. The p.e. spectrum of [Ru₂(O₂CCF₃)₄] has been unambigously assigned but the experimental data do not establish whether the ground-state electron configuration is σ²π⁴δ²π*³δ*¹ or σ²π⁴δ²π*²δ*². The calculations and p.e. spectra support a groundstate configuration of σ²π⁴δ²π*⁴δ*² for [Ru₂(O₂CCF₃)₄(NO)₂].