the pdf is a work on this topic. it goes through Larmor Precession and give example on spin-½ and spin-1 system.
then it introduce Density matrix and gives some example.
The Rabi resonance was treated by rotating frame method and using density matrix on discussion.
the last topic is on the relaxation.
the purpose of study it extensively, is the understanding on NMR.
the NMR signal is the transverse component of the magnetization.