UV–Vis Spectra of Gold(III) Complexes with Different Halides, Hydroxide, and Ammonia According to TD-DFT Calculations

This paper presents accurate TD-DFT calculations for several mixed-ligand gold(III) complexes with ligands including Cl−, Br−, I−, OH−, and NH3. The calculated results show excellent agreement with available experimental data. The spectral shapes are determined by charge transfer transitions, which are systematically influenced by the ligand’s position in the spectrochemical series. The main vertical electron transitions and the molecular orbitals involved are identified and discussed. Furthermore, the results indicate that the iodide-containing gold(III) complexes, [AuCl2I2]− and [AuI(OH)3]−, are viable candidates for practical synthesis.