Magnetic Relaxation of a Quadrupole Nucleus with Spin S = 1 in the Presence of Cross-Correlation Effects in an Anisotropic Medium

Autor: G. S. Kupriyanova
Rok vydání: 2005
Předmět:
Zdroj: Russian Physics Journal. 48:857-862
ISSN: 1573-9228
1064-8887
Popis: In the present work, a theoretical description of relaxation processes in a dipole-bonded two-spin system comprising a quadrupole nucleus with spin S = 1 and a nucleus with spin I = 1/2 is given. It is assumed that the stationary component of quadrupole-dipole interactions specifies energy levels of the quadrupole nucleus in a magnetic field, and the relaxation is determined by time-dependent dipole interactions between spins D(I S), quadrupole interaction of the nucleus Q(S), and chemical shift anisotropy of both nuclei CSA(I) and CSA(S). Interference (cross-correlation) terms for these interaction types D - Q, D - CSA, and D - CSA are also taken into account. Operator relaxation equations that describe transverse NMR relaxation of the nucleus with spin S = 1 in the second order of perturbation theory are derived in the context of density matrix theory. These relaxation equations are subsequently used to study transverse relaxation of each spectral component of the nucleus with spin S = 1. The rates of transverse relaxation and cross-correlation between the components are calculated.
Databáze: OpenAIRE