dc.contributor.author | Gee, Myrlene. | en_US |
dc.date.accessioned | 2014-10-21T12:36:20Z | |
dc.date.available | 2001 | |
dc.date.issued | 2001 | en_US |
dc.identifier.other | AAINQ66648 | en_US |
dc.identifier.uri | http://hdl.handle.net/10222/55777 | |
dc.description | The combination of solid-state NMR and theoretical calculations to characterize NMR parameters is applied to compounds containing P-P bonds where phosphorus participates in a variety of bonding modes. In particular, phosphorus chemical shift tensors and one-bond indirect spin-spin or J-coupling tensors, 1J(31P, 31P), have been investigated experimentally by NMR and complemented by first-principles calculations. | en_US |
dc.description | The phosphorus chemical shift and spin-spin coupling tensors for tetramethyldiphosphine disulfide are characterized by analysis of 31P NMR spectra obtained at 4.7 T for a single crystal. These results were compared to those obtained from spectra acquired at 4.7 T and 9.4 T for powder samples. The data obtained from both methods are in excellent agreement. It was also found that the upper limit on the anisotropy in 1J( 31P,31P), DeltaJ, is approximately 450 Hz. | en_US |
dc.description | The phosphorus chemical shift tensors for a phosphole tetramer were characterized by analysis of 31P NMR spectra acquired at 4.7 T and 9.4 T for powder samples. The experimental NMR results are supplemented by first principles calculations of the chemical shift tensor. The calculations are useful for proposing chemical shift tensor orientations. | en_US |
dc.description | The final example presented here is an investigation of the phosphinophosphonium salt, [Ph3P-PPh2][GaCl4]. The structure is not available from X-ray diffraction studies, thus characterization by other means, such as solid-state NMR, is important. To determine the P-P bond length from the effective dipolar coupling constant, Reff, Delta J needs to be estimated, in this case by ab initio calculations on a model system, H3P-PH2+. Combination of the calculated DeltaJ value and the measured Reff yields a P-P bond length of 2.25 A. Further calculations of 1J(31P, 31P) for H2P-PH2 offers an opportunity to investigate the dependence of this parameter on conformation. First-principles calculations allows one to map out the detailed orientation dependence as well as the potential energy surface. | en_US |
dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 2001. | en_US |
dc.language | eng | en_US |
dc.publisher | Dalhousie University | en_US |
dc.publisher | | en_US |
dc.subject | Chemistry, Physical. | en_US |
dc.title | Phosphorus chemical shift and indirect phosphorus-31-phosphorus-31 spin-spin coupling tensors in compounds containing phosphorus-phosphorus bonds: A solid-state phosphorus-31 NMR and theoretical study. | en_US |
dc.type | text | en_US |
dc.contributor.degree | Ph.D. | en_US |