Relaxation of Spin 1/2 in the Scalar Coupled Spin System AMX with Quadrupolar Nuclei in the Presence of Cross-correlation Effects
نویسنده
چکیده
We present the formal theory of the nuclear magnetic relaxation of spin 1/2 A in a scalar coupled spin system AMX with quadrupolar nuclei of spin 1 (M, X) considering cross-correlation relaxation based on second order time-dependent perturbation theory and the product operator formalism. The expressions for longitudinal and transverse relaxation times and dynamic frequency shifts of each component of the spectral pattern are derived. Several experimental schemes for the selective determination of the cross-correlation rate between different spin orders are proposed.
منابع مشابه
Selective cross-polarization in solution state nuclear magnetic resonance of scalar coupled spin 1 2 and quadrupolar nuclei
Semiselective heteronuclear cross-polarization for achieving coherence transfer between a spin I 5 2 scalar coupled to a spin S> 1 2 in isotropic solution is considered. The expansion of the density operator as products of irreducible tensor operators provides a compact formalism for describing cross-polarization involving scalar coupled quadrupolar nuclei. An analytical description of cross-po...
متن کاملRelaxation effects in a system of a spin-1/2 nucleus coupled to a quadrupolar spin subjected to RF irradiation: evaluation of broadband decoupling schemes.
We have investigated the suitability and performance of various decoupling methods on systems in which an observed spin-1/2 nucleus I (13C or 15N) is scalar-coupled to a quadrupolar spin S (2H). Simulations and experiments have been conducted by varying the strength of the irradiating radiofrequency (RF) field, RF offset, relaxation times, and decoupling schemes applied in the vicinity of the S...
متن کاملLineshape Variations of a Spin-1/2 Nucleus Coupled to a Quadrupolar Spin Subjected to RF Irradiation
In this paper, the lineshape variations in the multiplet structure fragments with a spin-2 and spin-1 directly bonded to each of a spin-12 nucleus I ( C) scalar coupled to a quadrupolar spin S other such as C– H, C– N, N– H, and H– N. All ( H) as a function of the strength of the irradiating radiofrequency these spin pairs have a J-coupling interaction between them. field applied in the vicinit...
متن کاملSolid-State Polarization-Transfer Experiments Involving Quadrupolar Nuclei
Historically, cross-polarization experiments [1,2] have been used to transfer spin coherence from abundant spins to a dilute spin system. Protons (*H) have been used almost exclusively as the source of strong nuclear polarization for cross-polarization experiments, although there have been some examples where other abundant nuclei have been used. Coupled with magic-angle spinning (MAS) NMR [3],...
متن کاملRelaxation Enhancement by Longitudinal Multispin Orders
Introduction: There is a great interest in increasing the longitudinal relaxation of nuclear spins for hyperpolarized imaging experiments. Longitudinal multispin orders (LOMO) correspond to the non-equilibrium population distribution and can be created in spin systems that exhibit J couplings, dipolar couplings or quadrupolar couplings (1). It can also be created via cross-correlated relaxation...
متن کامل