应用积算符理论研究弱耦合双自旋体系的Raman磁共振谱

从积算符理论和实验上详细地研究了弱耦合双自旋体系（CHCl₃的C-H双自旋体系）的Raman磁共振谱．对不同射频场强度及频偏的Raman谱进行了细致的理论和实验研究，表明积算符理论的计算与实验不仅在弱射频场而且在强射频场时都符合得相当好，克服了微扰论的局限，这为进一步研究复杂自旋体系的Raman谱提供了强有力的理论方法．研究还表明，小的射频频偏将有利于多量子跃迁信号的观测，而适当的射频场强则会提高多量子峰的强度 关键词：

DESCRIPTION OF RAMAN MAGNETIC RESONANCE SPECTROSCOPY IN WEAKLY COUPLED TWO-SPIN SYSTEM BY PRODUCT OPERATOR FORMALISM

Raman magnetic resonance (RMR) spectroscopy in weakly coupled two-spin system (C-H spin system in CHCl₃ molecule) has been investigated in detail by product operator formalism and RMR experiment, where the irradiated nucleus is proton and the detected nucleus is carbon. The theoretical results predicted by product operator formalism are in good agreement with the RMR experiment in various radio-frequency offsets and irradiation strengths applied to proton, indicating that product-operator formalism has advantages over the perturbation approximation-method and eliminates limitation of the approximation method that can be only used to describe the RMR experiment under the case of weak radio frequency irradiation. The studies also show that product operator formalism is a powerful tool for examining the RMR experiments in complex spin systems. It is found that the multiple quantum transitions are much easier to be observable with small radio frequency offsets and higher signal-to-noise ratio is obtained with the moderate irradiation strengths in RMR experiment.