title: Deuteron quadrupole coupling in benzene: librational corrections using a temperature-dependent Einstein model, and summary. The symmetries of electric field gradients and conditions for eta = 1.
abstract: Librational corrections are added to previous single-crystal and polycrystalline measurements of the deuteron quadrupole coupling constant in benzene. The results are related to gas-phase and liquid-crystal measurements and to theoretical values. A 'temperature-dependent Einstein model' is introduced for the purpose. The group-theoretical relations of the electric field-gradient (EFG) tensor to the nuclear site symmetry are discussed. The conditions for eta = 1 for reorientational processes are identified.
authors.affiliation: Department of Chemistry, University of Helsinki, P.O.B. 55 (A. I. Virtasen aukio 1), FIN-00014, Helsinki, Finland. Pekka.Pyykko@helsinki.fi
authors.forename: Pekka
authors.initials: P
authors.lastname: Pyykkö
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Elmi
mesh_terms: D001554:Benzene / Q000737:chemistry*; D003903:Deuterium / Q000737:chemistry*; D004583:Electrons; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D013696:Temperature; D014732:Vibration
chemical_list: D003903:Deuterium; D001554:Benzene