Density matrix calculation of spin pure nuclear quadrupole resonance echoes

Two-frequency imaging method for multi-level quadrupole systems

“…The question arises whether one can expect a similar result for q not zero. As an example, the exact solutions for I = 5/2 NQR Hamiltonian [13] show that with r = I the transition frequencies collapse into a single observable transition; therefore, pulses are not longer selective and single quantum and the above given treatment for the two frequency method is no longer applicable. Besides, the nutation frequencies associated with each transition are i -dependent and for r * 0 the simple assumed orientation dependence does not hold.…”

Homonuclear dipolar broadening of spin 5/2 pure nuclear quadrupole resonance line

“…Although the result of this work seems a simple theoretical one it is useful when measuring by means of non conventional method [5,6] second moments of both homonuclear, M2 ~I, and heteronuclear-quadrupolar, M2 ~s § contributions. Thus, the experimental results may be compared with the theoretical one, Eq.…”

“…Sucia a basis is spanned by the vectors~::=I--~2 {In,m)+[m,n>}; m*n [[m,m>;m n(6) where the orthonormal basis vectors and their subscript i = 1, 2 ..... 36, which labels the vectors, are explicitly listed in the Appendix.Two kinds of states may be distinguished; from [ ~> to I ~,> the states do not change sign under a particle exchange, these are identified as even parity states. The rest do change sign under a particle exchange and are odd parity states.…”

Probing the validity of average Hamiltonian theory for spin I=1, 3/2 and 5/2 nuclei by analyzing a simple two-pulse sequence

“…Haase and Oldfield investigated spin relaxation and linewidths of a variety of non-integer spins using an echo experiment and provided an analysis that accounts for the evolution of the spin system under the first-order quadrupolar interaction during the RF pulses [15]. Nagel et al have also reported on a density matrix calculation of spin echoes for spin 5/2 nuclei [16], and Pandey et al reported on the pulsed NMR signal of spin I = 3/2 nuclei [17].…”