Proton Spin Relaxation and Mobility in Hydrous Melts

Abstract

Pulse and continuous wave NMR measurements are reported for protons in hydrous melts of calcium nitrate at temperatures between --4 ~ and 120~ At temperatures near 50~ mean Arrhenius coefficients, AHT1 (kcal/mole), are 7.9, 7.3, and 4.8, respectively, for melts containing 2.8, 4.0, and 8.0 moles of water per mole of calcium nitrate, compared to 4.6 kcal/mole for pure water. Temperature dependence of T1 and T2 in Ca(NOj)2-2.8 H20 between --4 ~ and 120~ are non-Arrhenius and can be represented by a Fulcher-type equation with a "zero mobility temperature" (T0) of 225~ close to the value of To for solute diffusion, electrical conductance, and viscosity. Resolution of the relaxation rates into correlation times for intramolecular (rotational) and intermolecular (translational) diffusional motion is discussed in terms of the Bloembergen-Purcell-Pound and more recent models for dipolar relaxation. ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 35.8.11.2 Downloaded on 2015-06-14 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 35.8.11.2 Downloaded on 2015-06-14 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 35.8.11.2 Downloaded on 2015-06-14 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 35.8.11.2 Downloaded on 2015-06-14 to IP