When a nucleus aligned with a magnetic field,Bo,absorbs radiation frequency (Rf),it can change spin orientation to a higher energy spin state.By relaxing back to the parallel (+1/2)spin state,the nucleus is said to be in resonance.Hence, NMR BWhen a nucleus aligned with a magnetic field, B0 , absorbs radiation frequency (Rf), it can change spin orientation to a higher energy spin state. By relaxing back to the parallel (+1/2) spin state, the nucleus is said to be in resonance. Hence, NMR