ELECTRONIC AND NUCLEAR PARAMAGNETISM AND ENERGY EXCHANGE MECHANISMS.
Abstract
In this experimentation it has been shown that the Na and Li nuclear magnetic resonance signal may be enhanced in NaCl and LiF by the EPR pumping of 'forbidden' transitions in which advantage is taken of the coupling between the Cl2(-) center or the F2(-) center and the host alkali nucleus. Evidently these centers affect the adjacent anion nuclei first and then this local polarization becomes rapidly diffused from one alkali nucleus to the next. This requires a spin diffusion rate which is fast compared to the nuclear spin lattice relaxation rate. A successful phenomenological theory has been developed to explain these effects at liquid N2 temperatures. An enhancement of 18 of the A127 nuclear magnetic signal by means of the Solid Effect has been observed at 78K in a sample of Al203 doped with small amounts of Cr(III). Will the data on the Al in Cr(III) doped Al2O3 follow the proposed phenomenological theory of the Solid State Effect. The basic work on spin diffusion as summarized in Section 4 should provide a solid theoretical foundation for the phenomenological theory. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1964
- Accession Number
- AD0611184
Entities
People
- R. F. O'brien
- R. K. Jeck
- S. K. Misra
- W. A. Barker
Organizations
- Saint Louis University