Analytical expression for the spin-5/2 line intensities

Abstract

The density matrix of a spin I = 5/2 excited by a radiofrequency pulse is calculated. The interaction involved during the excitation of the spin system is first order quadrupolar. Consequently, the results are valid for any ratio of the quadrupolar coupling, θ_Q to the pulse amplitude θ_RF. The behaviour of the central and the two satellite line intensities versus the pulse length is discussed. The aluminium nuclei (²⁷Al) in a single crystal of corundum (Al₂O₃) are used to illustrate some results.