Application of High Frequency EPR to Integer Spin Systems: Unusual Behavior of the Double-Quantum Line
✍ Scribed by Pieter J. van Dam; Adri A.K. Klaassen; Eduard J. Reijerse; Wilfred R. Hagen
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 143 KB
- Volume
- 130
- Category
- Article
- ISSN
- 1090-7807
No coin nor oath required. For personal study only.
✦ Synopsis
A high-frequency EPR study is presented of the integer spin sys-S Å 1 but is EPR silent at conventional frequencies (13) due tem Ni(II) in the host of Zn-tris(ethylenediamine) dinitrate. This to the large ZFS. High-frequency EPR would be a useful tool complex shows a broad structureless line at X band. At D band (130 to accurately measure the ZFS parameters of this system. As GHz) however, a standard triplet powder spectrum is observed. a spectroscopic model complex for these type of nickel sys-Superimposed on this spectrum is a ''double-quantum'' line at the tems we have studied a powder of Ni(II)-doped zinc-trisexpected position. The microwave power dependency of this line is (ethylenediamine)dinitrate, [Zn(en) 3 ](NO 3 ) 2 . We have defound to be in contradiction with existing theory on multiple-quantected a strong ''double-quantum'' line in the powder triplet tum transitions. The line in our spectra shows a single quantum line spectra of this Ni(II) complex at a frequency of 130 GHz.
behavior in intensity and linewidth as a function of the microwave
The unusual behavior of this line is compared to data available frequency from 35 to 130 GHz. A literature survey leads to the in the EPR literature on double-quantum transitions.
conclusion that most double-quantum features in high-spin systems do not follow the P 3/2 power dependency predicted by second-order Purple crystals of Ni(II) doped into Zn(en) 3 (NO 3 ) 2 were perturbation theory. In our case the double-quantum line is assigned grown as described by Sreeramachandra Prasad and Subrato an enhancement effect due to the simultaneous excitation of two manian (11) with a nickel concentration of 4%. Crystals single-quantum transitions.