Nuclear relaxation in an antiferromagnetic single crystal

Syntheses, Structural, and Physical Studies of Basic CrIII and FeIII Benzilates and Benzoates: Evidence of Antisymmetric Exchange and Distributions of Isotropic and Antisymmetric Exchange Parameters

“…In this model the NMR relaxation is caused by the local field fluctuations originating from the magnetic excitations from the ground state to the excited state, separated by the energy difference ∆. Assuming that the Cr III spin system remains in the ground state for an average time τ 0 and in the excited state for a lifetime τ 1 , during which an effective transverse local field h Ќ appears at the nuclear site, the relaxation rate is expressed as [Equation (5)]: [41] Basic Cr III and Fe III Benzilates and Benzoates FULL PAPER (5) where γ N is the proton gyromagnetic ratio, and ω N is the Larmor angular frequency. This model has been frequently employed for the nuclear magnetic relaxation in paramagnets.…”

Magnetic critical behavior in the[Cu(1−hydroxybenzotriazolate)2(MeOH)Fardis1, Christides2, Diamantopoulos3 et al. 2003Phys. Rev. B2000View full textAdd to dashboardCite

“…In addition, various interpolation procedures, which combine moment expansions at short times and diffusive decay at long times, have been particularly successful. 27 In this section we demonstrate that a simple model that is based on a two-level scheme 28 for the fluctuations of the orientation of the magnetic moment is adequate to describe our T 1 relaxation data close to and above the transition temperature. This model has been originally proposed by Hardeman et al 28 and it was frequently employed for the nuclearmagnetic relaxation in paramagnets.…”

“…27 In this section we demonstrate that a simple model that is based on a two-level scheme 28 for the fluctuations of the orientation of the magnetic moment is adequate to describe our T 1 relaxation data close to and above the transition temperature. This model has been originally proposed by Hardeman et al 28 and it was frequently employed for the nuclearmagnetic relaxation in paramagnets. 18,29,30 The main assumption of the model is that during a certain average lifetime 1 the magnetic moment in a Cu ion is directed parallel to the time average magnetization ͗M ͘ whereas during an average lifetime 2 is antiparallel to it.…”

Nuclear Magnetic Resonance in Ferromagnets and Antiferromagnets

“…Equation (76) has been used to explain experimental measurements of the nuclear spin-lattice relaxation rate of protons in antiferromagnetic CuC1, ' 2H20) [88] and fluorine nuclei in antiferromagnetic MnF, [89]. In CuC1, -2H20 the spin-lattice relaxation rate was found to vary a s sin2 8, where B was varied by using a magnetic field applied perpendicular to the axis of quantization of the electron spins.…”