A HF/CI-SD study of the low-lying states of nitroprusside ion
Autor(a) principal: | |
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Data de Publicação: | 1997 |
Outros Autores: | |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Journal of the Brazilian Chemical Society (Online) |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000500010 |
Resumo: | Since the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Na2Fe(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 p* (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-zetaF quality basis set. The ab initio results support Bottomley and Greins 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 (d xz,d yz ® p* NO) have been estimated to be at 4.52 eV and show a rather intense absorption band. The second CT excitation, 1b2 ® 13e (d xy ® p* 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 HOMOs. 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. |
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A HF/CI-SD study of the low-lying states of nitroprusside ionab initio (SCF,CI-SD)nitroprussideexcited statesmetastable statesNa2Fe(CN)5NOpentacyanonitrosylferrateSince the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Na2Fe(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 p* (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-zetaF quality basis set. The ab initio results support Bottomley and Greins 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 (d xz,d yz ® p* NO) have been estimated to be at 4.52 eV and show a rather intense absorption band. The second CT excitation, 1b2 ® 13e (d xy ® p* 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 HOMOs. 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.Sociedade Brasileira de Química1997-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000500010Journal of the Brazilian Chemical Society v.8 n.5 1997reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50531997000500010info:eu-repo/semantics/openAccessHollauer,EduardoOlabe,José A.eng2010-09-10T00:00:00Zoai:scielo:S0103-50531997000500010Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2010-09-10T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false |
dc.title.none.fl_str_mv |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
title |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
spellingShingle |
A HF/CI-SD study of the low-lying states of nitroprusside ion Hollauer,Eduardo ab initio (SCF,CI-SD) nitroprusside excited states metastable states Na2Fe(CN)5NO pentacyanonitrosylferrate |
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 |
A HF/CI-SD study of the low-lying states of nitroprusside ion |
author |
Hollauer,Eduardo |
author_facet |
Hollauer,Eduardo Olabe,José A. |
author_role |
author |
author2 |
Olabe,José A. |
author2_role |
author |
dc.contributor.author.fl_str_mv |
Hollauer,Eduardo Olabe,José A. |
dc.subject.por.fl_str_mv |
ab initio (SCF,CI-SD) nitroprusside excited states metastable states Na2Fe(CN)5NO pentacyanonitrosylferrate |
topic |
ab initio (SCF,CI-SD) nitroprusside excited states metastable states Na2Fe(CN)5NO pentacyanonitrosylferrate |
description |
Since the discovering of two photoexcited metastable states of crystalline sodium nitroprusside, Na2Fe(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 p* (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-zetaF quality basis set. The ab initio results support Bottomley and Greins 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 (d xz,d yz ® p* NO) have been estimated to be at 4.52 eV and show a rather intense absorption band. The second CT excitation, 1b2 ® 13e (d xy ® p* 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 HOMOs. 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. |
publishDate |
1997 |
dc.date.none.fl_str_mv |
1997-01-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000500010 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531997000500010 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-50531997000500010 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
publisher.none.fl_str_mv |
Sociedade Brasileira de Química |
dc.source.none.fl_str_mv |
Journal of the Brazilian Chemical Society v.8 n.5 1997 reponame:Journal of the Brazilian Chemical Society (Online) instname:Sociedade Brasileira de Química (SBQ) instacron:SBQ |
instname_str |
Sociedade Brasileira de Química (SBQ) |
instacron_str |
SBQ |
institution |
SBQ |
reponame_str |
Journal of the Brazilian Chemical Society (Online) |
collection |
Journal of the Brazilian Chemical Society (Online) |
repository.name.fl_str_mv |
Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ) |
repository.mail.fl_str_mv |
||office@jbcs.sbq.org.br |
_version_ |
1750318163069763584 |