In this paper, quantum coherences under weak interaction in A, AX, AMX and AFMX systems of which spin quantum number 1/2is,and in A and AX systems of which spin guantum number is 3/2 are calculated by using the density matrix.

• 本文用密度矩阵计算了在弱相互作用下,自旋都为1/2的核的A、AX、AMX与AFMX四种体系以及自旋都为3/2的核的A与AX两种体系中的各种量子相干。