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Published on: June 28, 2018
The Blue-Violet Color of Pentamethylbismuth: A Visible Spin-Orbit Effect
Jeanet Conradie1, Abhik Ghosh2
1Department of Chemistry University of the Free State 9300 Bloemfontein Republic of South Africa.
Abstract:
Two-component relativistic time-dependent density functional theory calculations with spin-orbit coupling predict yellow and orange-red absorption for BiPh5 and BiMe5, respectively, providing an excellent explanation for their respective violet and blue-violet colors. According to the calculations, the visible absorption is clearly attributable to a single transition from a ligand-based HOMO to a low-energy LUMO with a significant contribution from a relativistically stabilized Bi 6s orbital. Surprisingly, scalar releativistic calculations completely fail to reproduce the observed visible absorption and place it at the violet/near-UV borderline instead.
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