A HF/CI-SD study of the low-lying states of nitroprusside ion
Since the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Nd2[Fe(CN)5NO].2H2O (SNP), showing rather long lifetimes at temperatures below 160 K, much effort has been devoted toward the study of its electronic structure. Despite this tremendous effort the nature...
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1997
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01035053_v8_n5_p495_Hollauer http://hdl.handle.net/20.500.12110/paper_01035053_v8_n5_p495_Hollauer |
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paper:paper_01035053_v8_n5_p495_Hollauer2023-06-08T15:10:24Z A HF/CI-SD study of the low-lying states of nitroprusside ion Ab initio (SCF,CI-SD) Excited states Metastable states Na2[Fe(CN)5NO] Nitroprusside Pentacyanonitrosylferrate Since the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Nd2[Fe(CN)5NO].2H2O (SNP), showing rather long lifetimes at temperatures below 160 K, much effort has been devoted toward the study of its electronic structure. Despite this tremendous effort the nature of the frontier orbitals and the related low energy excitations remains controversial. Early calculations, EHT, showed the HOMO as mainly the metallic 3d orbital while the LUMO had a major π* (NO) contribution. However INDO calculations, clearly set the metal d orbital many electron-volts deep in core. The vertical electronic spectrum have been estimated through ab initio HF/CI-SD with a double-zeta quality basis set. The ab initio results support Bottomley and Grein's interpretations and assign the first electronic transitions to ligand-to-ligand charge-transfer excitation from trans-cyano to nitrosyl ligands. The corresponding oscillator strengths have been calculated showing comparable intensity with the experimental results. The excitation energy of the metal → NO charge-transfer transition, 8e → 13e (dxz,dyz → π* NO) have been estimated to be at 4.52 eV and show a rather intense absorption band. The second CT excitation, 1b2 →13e (dxy → π* NO), pointed by previous works as a typical CT band, exhibits a small intensity at 5.04 eV. In the calculations it was observed that SCF orbital ordering are rather dependent on the metal basis set used. Metallic minimal basis set show results in close agreement with EHT early calculations while double-zeta basis set pushes the metallic d orbitals deep away from the HOMO's. The HF orbital ordering has been used to interpret photochemical and thermoanalysis experiments on SNP and the results seem to fit properly with the calculated properties. 1997 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01035053_v8_n5_p495_Hollauer http://hdl.handle.net/20.500.12110/paper_01035053_v8_n5_p495_Hollauer |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Ab initio (SCF,CI-SD) Excited states Metastable states Na2[Fe(CN)5NO] Nitroprusside Pentacyanonitrosylferrate |
| spellingShingle |
Ab initio (SCF,CI-SD) Excited states Metastable states Na2[Fe(CN)5NO] Nitroprusside Pentacyanonitrosylferrate A HF/CI-SD study of the low-lying states of nitroprusside ion |
| topic_facet |
Ab initio (SCF,CI-SD) Excited states Metastable states Na2[Fe(CN)5NO] Nitroprusside Pentacyanonitrosylferrate |
| description |
Since the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Nd2[Fe(CN)5NO].2H2O (SNP), showing rather long lifetimes at temperatures below 160 K, much effort has been devoted toward the study of its electronic structure. Despite this tremendous effort the nature of the frontier orbitals and the related low energy excitations remains controversial. Early calculations, EHT, showed the HOMO as mainly the metallic 3d orbital while the LUMO had a major π* (NO) contribution. However INDO calculations, clearly set the metal d orbital many electron-volts deep in core. The vertical electronic spectrum have been estimated through ab initio HF/CI-SD with a double-zeta quality basis set. The ab initio results support Bottomley and Grein's interpretations and assign the first electronic transitions to ligand-to-ligand charge-transfer excitation from trans-cyano to nitrosyl ligands. The corresponding oscillator strengths have been calculated showing comparable intensity with the experimental results. The excitation energy of the metal → NO charge-transfer transition, 8e → 13e (dxz,dyz → π* NO) have been estimated to be at 4.52 eV and show a rather intense absorption band. The second CT excitation, 1b2 →13e (dxy → π* NO), pointed by previous works as a typical CT band, exhibits a small intensity at 5.04 eV. In the calculations it was observed that SCF orbital ordering are rather dependent on the metal basis set used. Metallic minimal basis set show results in close agreement with EHT early calculations while double-zeta basis set pushes the metallic d orbitals deep away from the HOMO's. The HF orbital ordering has been used to interpret photochemical and thermoanalysis experiments on SNP and the results seem to fit properly with the calculated properties. |
| title |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
| title_short |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
| title_full |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
| title_fullStr |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
| title_full_unstemmed |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
| title_sort |
hf/ci-sd study of the low-lying states of nitroprusside ion |
| publishDate |
1997 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01035053_v8_n5_p495_Hollauer http://hdl.handle.net/20.500.12110/paper_01035053_v8_n5_p495_Hollauer |
| _version_ |
1768542830573125632 |