Affiliation:
1. Chemistry Department, Queen’s University, Kingston Ont K7L 3N6, Canada
Abstract
Abstract
The temperature dependence of the spin-lattice relaxation time T1 for the Re NQR in KReO4 , NH4ReO4 and ND4ReO4 has been measured between 77 K and 323 K. The relaxation is electric quadrupolar in all cases, and because of the large quadrupole moment of Re, T1 is short. In KReO4 T1 follows a T2 dependence. In NH4ReO4 , T1 decreases more rapidly than T-2 above about 100 K; between 170 K and 250 K T1 is smaller than 100 (is and could not be measured, but above 250 K, T1 increases to about 140 μs, and the measured data near room temperature lie close to the T-2 extrapolation from the T1 values below 100 K. These results are interpreted as normal anharmonic Raman quadrupolar relaxation, with a T-2 dependence on temperature, combined with an additional relaxation process due to switching of the ammonium ion between two possible orientations.
Subject
Physical and Theoretical Chemistry,General Physics and Astronomy,Mathematical Physics
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献