M. Monduzzi , A. Lai , G. Saba , M. Casu , G. Crisponi
{"title":"多巴胺Co(II)复合物的C-13磁弛豫率和H-1和C-13顺磁位移","authors":"M. Monduzzi , A. Lai , G. Saba , M. Casu , G. Crisponi","doi":"10.1016/0378-4487(82)80056-3","DOIUrl":null,"url":null,"abstract":"<div><p>The importance of unpaired spin distribution in the Co(II)-Dopamine complex in aqueous solution, was investigated. From the analysis of the H-1 and C-13 isotropic shifts and with the aid of an INDO M.O. calculation on a dopamine radical a prevalent σ-type delocalization mechanism of the spin density was evidentiated, even if a contribution from π-electrons cannot be completely excluded.</p><p>The analysis of the spin-lattice relaxation rates revealed the importance of ligand-centered dipolar interactions. The introduction of the spin densities, calculated from the INDO method, in the modified Solomon-Bloembergen equation, allowed to estimate the correlation time of the complex which can be identified with the electronic relaxation time.</p></div>","PeriodicalId":100049,"journal":{"name":"Advances in Molecular Relaxation and Interaction Processes","volume":"24 4","pages":"Pages 233-244"},"PeriodicalIF":0.0000,"publicationDate":"1982-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0378-4487(82)80056-3","citationCount":"5","resultStr":"{\"title\":\"C-13 magnetic relaxation rates and H-1 and C-13 paramagnetic shifts of Co(II) complex of dopamine\",\"authors\":\"M. Monduzzi , A. Lai , G. Saba , M. Casu , G. Crisponi\",\"doi\":\"10.1016/0378-4487(82)80056-3\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The importance of unpaired spin distribution in the Co(II)-Dopamine complex in aqueous solution, was investigated. From the analysis of the H-1 and C-13 isotropic shifts and with the aid of an INDO M.O. calculation on a dopamine radical a prevalent σ-type delocalization mechanism of the spin density was evidentiated, even if a contribution from π-electrons cannot be completely excluded.</p><p>The analysis of the spin-lattice relaxation rates revealed the importance of ligand-centered dipolar interactions. The introduction of the spin densities, calculated from the INDO method, in the modified Solomon-Bloembergen equation, allowed to estimate the correlation time of the complex which can be identified with the electronic relaxation time.</p></div>\",\"PeriodicalId\":100049,\"journal\":{\"name\":\"Advances in Molecular Relaxation and Interaction Processes\",\"volume\":\"24 4\",\"pages\":\"Pages 233-244\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1982-12-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1016/0378-4487(82)80056-3\",\"citationCount\":\"5\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Advances in Molecular Relaxation and Interaction Processes\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/0378448782800563\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Advances in Molecular Relaxation and Interaction Processes","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0378448782800563","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
C-13 magnetic relaxation rates and H-1 and C-13 paramagnetic shifts of Co(II) complex of dopamine
The importance of unpaired spin distribution in the Co(II)-Dopamine complex in aqueous solution, was investigated. From the analysis of the H-1 and C-13 isotropic shifts and with the aid of an INDO M.O. calculation on a dopamine radical a prevalent σ-type delocalization mechanism of the spin density was evidentiated, even if a contribution from π-electrons cannot be completely excluded.
The analysis of the spin-lattice relaxation rates revealed the importance of ligand-centered dipolar interactions. The introduction of the spin densities, calculated from the INDO method, in the modified Solomon-Bloembergen equation, allowed to estimate the correlation time of the complex which can be identified with the electronic relaxation time.