2H NMR Patterns of Methylaromatics Adsorbed on Graphite

Abstract

2H NMR solid state powder patterns were measured at one monolayer coverage of benzene on the non graphitized carbon black Spheron, and of toluene, p-xylene, mesitylene, and mellitene (hexamethylbenzene) on the graphitized carbon black Graphon. Benzene on Spheron, in contrast to Graphon, exhibits a typical Pake type powder pattern shape demonstrating the minor influence of paramagnetic centers on the pattern shapes as well as confirming the formerly introduced shielding anisotropy interaction in the case of graphite. From the highly asymmetric appearance of the 2H powder patterns for the adsorbed methyl-aromatics on Graphon the flat orientation of these molecules on graphite as well as details of the rotational molecular motions are deduced.