Dc. Doetschman et Gd. Thomas, ELECTRON-SPIN DEPHASING MODEL FOR MOLECULAR-REORIENTATION - EXACT-SOLUTIONS, Chemical physics letters, 232(3), 1995, pp. 242-246
Electron spin coherence decay was recently applied to the molecular re
orientation of spin probes. We employed the approximation of Van 't Ho
f and Schmidt [C.A. Van't Hof and J. Schmidt, Chem. Phys. Letters 36 (
1975) 460]. The approximation was not strictly applicable at low reori
entation rates. We found the exact solutions to the coupled differenti
al equations governing the magnetization. The real and imaginary parts
of the characteristic matrix yield rate constants and resonance frequ
ency shifts, respectively. The predicted temperature dependence of the
coherence decay rates gives a narrower peak and is in better agreemen
t with experiment.