Gurpreet Singh , Usha D. Phalgune , Perunthiruthy K. Madhu , Niels Chr. Nielsen , Subramanian Ganapathy
{"title":"用固体核磁共振波谱和从头计算确定5 ' -三磷酸腺苷三水合物二钠的化学屏蔽和电场梯度张量","authors":"Gurpreet Singh , Usha D. Phalgune , Perunthiruthy K. Madhu , Niels Chr. Nielsen , Subramanian Ganapathy","doi":"10.1016/j.jmro.2022.100051","DOIUrl":null,"url":null,"abstract":"<div><p>The tri-phosphate and sodium ion environments in well crystallized disodium 5′adenosine triphosphate trihydrate (ATP•3H<sub>2</sub>O) are investigated using high-resolution solid-state NMR spectroscopy and <em>ab initio</em> calculations. The six inequivalent phosphorus sites resolved in <sup>31</sup>P MAS spectra have been assigned on the basis of experimentally obtained results and theoretical <em>ab initio</em> quantum chemical calculations of <sup>31</sup>P chemical shielding tensors with increased numerical accuracy. Aided by <sup>31</sup>P-<sup>31</sup>P dipolar connectivity established in DQ-SQ correlation experiment and DFT calculations carried out at the B3LYP/(aug-cc-pDVZ(3s,2p,1d), 6–31G(d,p)) level, phosphorus resonance assignments in MAS spectra have been made and the <sup>31</sup>P chemical shielding anisotropies and tensor orientations in the molecule-fixed frame have been determined. <sup>31</sup>P shielding tensors are found to be oriented with the most shielded direction nearly perpendicular to the O-P-O plane involving the two adjoining oxygens. The complete resolution of the four sodium sites has been achieved from 3Q-MAS experiments performed at 7.05 T and this has enabled <sup>23</sup>Na quadrupole parameters to be determined experimentally and compared with theoretical calculations. Besides aiding a partial resonance assignment of the <sup>23</sup>Na 3Q-MAS spectrum, our HF/6–311++<em>G</em>(2d,2p) calculations of <sup>23</sup>Na EFG tensors show that for two sodium sites which are tightly coordinated the orientation of the EFG tensor is distinct. These exhibit unique directions along which the field gradient is the smallest and largest.</p></div>","PeriodicalId":365,"journal":{"name":"Journal of Magnetic Resonance Open","volume":null,"pages":null},"PeriodicalIF":2.6240,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Chemical shielding and electric field gradient tensors of disodium 5′-adenosine triphosphate trihydrate determined by solid-state NMR spectroscopy and ab initio calculations\",\"authors\":\"Gurpreet Singh , Usha D. Phalgune , Perunthiruthy K. Madhu , Niels Chr. Nielsen , Subramanian Ganapathy\",\"doi\":\"10.1016/j.jmro.2022.100051\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The tri-phosphate and sodium ion environments in well crystallized disodium 5′adenosine triphosphate trihydrate (ATP•3H<sub>2</sub>O) are investigated using high-resolution solid-state NMR spectroscopy and <em>ab initio</em> calculations. The six inequivalent phosphorus sites resolved in <sup>31</sup>P MAS spectra have been assigned on the basis of experimentally obtained results and theoretical <em>ab initio</em> quantum chemical calculations of <sup>31</sup>P chemical shielding tensors with increased numerical accuracy. Aided by <sup>31</sup>P-<sup>31</sup>P dipolar connectivity established in DQ-SQ correlation experiment and DFT calculations carried out at the B3LYP/(aug-cc-pDVZ(3s,2p,1d), 6–31G(d,p)) level, phosphorus resonance assignments in MAS spectra have been made and the <sup>31</sup>P chemical shielding anisotropies and tensor orientations in the molecule-fixed frame have been determined. <sup>31</sup>P shielding tensors are found to be oriented with the most shielded direction nearly perpendicular to the O-P-O plane involving the two adjoining oxygens. The complete resolution of the four sodium sites has been achieved from 3Q-MAS experiments performed at 7.05 T and this has enabled <sup>23</sup>Na quadrupole parameters to be determined experimentally and compared with theoretical calculations. Besides aiding a partial resonance assignment of the <sup>23</sup>Na 3Q-MAS spectrum, our HF/6–311++<em>G</em>(2d,2p) calculations of <sup>23</sup>Na EFG tensors show that for two sodium sites which are tightly coordinated the orientation of the EFG tensor is distinct. These exhibit unique directions along which the field gradient is the smallest and largest.</p></div>\",\"PeriodicalId\":365,\"journal\":{\"name\":\"Journal of Magnetic Resonance Open\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.6240,\"publicationDate\":\"2022-06-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Magnetic Resonance Open\",\"FirstCategoryId\":\"1\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2666441022000218\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Magnetic Resonance Open","FirstCategoryId":"1","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2666441022000218","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Chemical shielding and electric field gradient tensors of disodium 5′-adenosine triphosphate trihydrate determined by solid-state NMR spectroscopy and ab initio calculations
The tri-phosphate and sodium ion environments in well crystallized disodium 5′adenosine triphosphate trihydrate (ATP•3H2O) are investigated using high-resolution solid-state NMR spectroscopy and ab initio calculations. The six inequivalent phosphorus sites resolved in 31P MAS spectra have been assigned on the basis of experimentally obtained results and theoretical ab initio quantum chemical calculations of 31P chemical shielding tensors with increased numerical accuracy. Aided by 31P-31P dipolar connectivity established in DQ-SQ correlation experiment and DFT calculations carried out at the B3LYP/(aug-cc-pDVZ(3s,2p,1d), 6–31G(d,p)) level, phosphorus resonance assignments in MAS spectra have been made and the 31P chemical shielding anisotropies and tensor orientations in the molecule-fixed frame have been determined. 31P shielding tensors are found to be oriented with the most shielded direction nearly perpendicular to the O-P-O plane involving the two adjoining oxygens. The complete resolution of the four sodium sites has been achieved from 3Q-MAS experiments performed at 7.05 T and this has enabled 23Na quadrupole parameters to be determined experimentally and compared with theoretical calculations. Besides aiding a partial resonance assignment of the 23Na 3Q-MAS spectrum, our HF/6–311++G(2d,2p) calculations of 23Na EFG tensors show that for two sodium sites which are tightly coordinated the orientation of the EFG tensor is distinct. These exhibit unique directions along which the field gradient is the smallest and largest.