Mössbauer spectra of novel gold compounds and their implications for the assignment of molecular structures

¹⁹⁷Au Mössbauer spectra have been recorded for a series of di- and trinuclear complexes of gold in different oxidation states and coordination numbers. While the interpretation of isomer shift and quadrupole coupling data is straightforward at least for groups of closely related compounds, the correlation of the line intensities with the molecular structure is more problematic. The results show that the relative line intensities in the spectra are largely determined by intramolecular motions. The recoil-free fractions may differ so much that stoichiometry-related structure assignments become hazardous.