| DOI | Resolve DOI: https://doi.org/10.1063/1.1405436 |
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| Author | Search for: Andruniow, Tadeusz; Search for: Kozlowski, Pawel M.; Search for: Zgierski, Marek Z.1 |
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| Affiliation | - National Research Council of Canada. NRC Steacie Institute for Molecular Sciences
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| Format | Text, Article |
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| Subject | molecular biophysics; orbital calculations; organic compounds; spectra; transition moments; ultraviolet spectra |
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| Abstract | Time-dependent density-functional theory (TD-DFT) is applied to analyze the electronic absorption spectra of vitamin B₁₂. To accomplish this two model systems were considered: CN-[CoIII-corrin]-CN (dicyanocobinamide, DCC) and imidazole-[CoIII-corrin]-CN (cyanocobalamin, ImCC). For both models 30 lowest excited states were calculated together with transition dipole moments. When the results of TD-DFT calculations were directly compared with experiment it was found that the theoretical values systematically overestimate experimental data by approximately 0.5 eV. The uniform adjustment of the calculated transition energies allowed detailed analysis of electronic absorption spectra of vitamin B₁₂ models. All absorption bands in spectral range 2.0�5.0 eV were readily assigned. In particular, TD-DFT calculations were able to explain the origin of the shift of the lowest absorption band caused by replacement of the�CN axial ligand by imidazole. |
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| Publication date | 2001-10-22 |
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| In | |
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| Language | English |
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| Peer reviewed | Yes |
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| NPARC number | 12333675 |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | 4bb39b5a-14b9-42b2-851a-e50af88210de |
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| Record created | 2009-09-10 |
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| Record modified | 2020-03-27 |
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