Synthesis, crystal, molecular and electronic structure of the [Re(NO)0.87Br2.13(PPh3)(PPh2py-P,N)] complex and DFT calculations of [Re(NO)Br2(PPh3)(PPh2py- P,N)]

A new rhenium nitrosyl complex – [Re(NO)0.87Br2.13(PPh3)(PPh2py-P,N)] – has been obtained in the reaction of [ReBr3(NO)(PPh3)(OPPh3)] with diphenyl(2-pyridyl)phosphine (PPh2py). The compound has been studied by IR, UV–vis spectroscopy and X-ray crystallography. The molecular orbital diagram of [Re(NO)Br2(PPh3)(PPh2py-P,N)] has been calculated with the density functional theory (DFT) method. The spin-allowed singlet–singlet electronic transitions of [Re(NO)Br2(PPh3)(PPh2py-P,N)] have been calculated with the time-dependent DFT method, and the UV–vis spectrum of the [Re(NO)0.87Br2.13(PPh3)(PPh2py-P,N)] compound has been discussed on this basis.