Direct determination of single-crystal parameters for axial paramagnetic resonance centers in polycrystalline-amorphous substances
Lee, Sook ; Brown, I. M. ; Ames, D. P.
College Park, Md. : American Institute of Physics (AIP)
Published 1985
College Park, Md. : American Institute of Physics (AIP)
Published 1985
| ISSN: |
1089-7690
|
|---|---|
| Source: |
AIP Digital Archive
|
| Topics: |
Physics
Chemistry and Pharmacology
|
| Notes: |
The paramagnetic resonance powder spectrum of an electron or nuclear spin system involving an isotropic Zeeman and an axially symmetric, first-order fine-structure splitting has been numerically investigated for the purpose of finding a simple, direct, and accurate method for determining its single-crystal parameters in polycrystalline-amorphous samples. It is shown that from the positions and relative intensities of some selected first- and second-derivative peaks of the axial fine-structure powder spectrum, one can directly determine with high accuracy the associated coupling constant, single-crystal line shape, and single-crystal linewidth for the external magnetic field perpendicular as well as parallel to the axially symmetric axis. The results of an experimental application of this method to the case of a randomly oriented zinc chelate biradical system are presented. The new powder spectrum method is applicable to first-order axially symmetric ESR and NMR quadrupole and dipole-dipole pair centers with isotropic g values under rigid state or slow tumbling orientational motion in polycrystalline-amorphous substances.
|
| Type of Medium: |
Electronic Resource
|
| URL: |