Conformational dynamics of a metallomesogen studied by H-2-NMR spectroscopy

In this work we present a quantitative analysis of both quadrupolar splitti ngs and deuterium Zeeman and quadrupolar spin-lattice relaxation times repo rted in the literature for two isotopomers of Azpac, an acetylacetonate der ivative of the cyclopalladated 4,4'-bis(hexyloxy) azoxybenzene. Azpac-d(4) is deuterated at the aromatic rings and Azpac-d(26) is deuterated on the al koxy chains. The additive potential method is used to model the splittings, while the derived spectral densities are interpreted using the decoupled m odel in conjunction with the Nordio model. The two side chains are assumed to be noninteracting and identical in their conformations in order to limit the size of the transition rate matric; needed to describe correlated inte rnal bond rotations in the chains. Rotational diffusion constants and inter nal jump rate constants are derived for this metallomesogen.