Zeeman Effect on the PMDR Signal and the Mechanism of the Intersystem Crossing Process in Pyrazine at 1.6K.

摘要

The observed change in the 10.38 GHz PMDR signal of pyrazine in durene at 1.6K upon the application of a magnetic field of 0-500 Gauss cannot be explained by the direct S sub 1(n,pi*) to T sub 1(n,pi*) intersystem crossing process. The observed results can be computer fitted if the crossing is assumed to involve an intermediate triplet state with zero-field parameters similar to those of the lowest pi,pi* state of substituted benzene. The relative probability of the direct to the indirect crossing to the different spin levels is concluded. The limitations of the method are discussed.