General treatment of paramagnetic relaxation enhancement associated with translational diffusion
2009 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 130, -174104 p.Article in journal (Refereed) Published
A theory of nuclear spin relaxation in isotropic liquids for nuclear spins interacting with electron spins, residing in other molecules (the outer-sphere relaxation), is presented. The approach, valid outside of the Redfield limit for electron spin relaxation, is an extension of the Swedish slow motion theory [ Benetis et al., Mol. Phys. 48, 329 (1983) ; Nilsson and Kowalewski, J. Magn. Reson. 146, 345 (2000) ] for inner-sphere relaxation. It is demonstrated that the outer-sphere relaxation rate can be expressed as an integral of a product of a translational diffusion correlation function and a function analogous to the inner-sphere spectral density. A numerical implementation of the theory is described and applied to a large number of realistic parameter sets for S = 7/2 and S = 1, which may correspond to Gd(III) and Ni(II) systems. It is shown that the outer-sphere contribution is relevant and should be included into the analysis of nuclear magnetic relaxation dispersion relaxation profiles, especially for slow relative translational diffusion and fast molecular tumbling
Place, publisher, year, edition, pages
2009. Vol. 130, -174104 p.
diffusion, gadolinium compounds, nickel compounds, nuclear magnetic resonance, nuclear spin-lattice relaxation, organic compounds
Research subject Physical Chemistry
IdentifiersURN: urn:nbn:se:su:diva-35494DOI: 10.1063/1.3119635ISI: 000266263100006OAI: oai:DiVA.org:su-35494DiVA: diva2:288931