title: Feasibility of arsenic and antimony NMR spectroscopy in solids: an investigation of some group 15 compounds.
abstract: The feasibility of obtaining (75)As and (1)(21/123)Sb NMR spectra for solids at high and moderate magnetic field strengths is explored. Arsenic-75 nuclear quadrupolar coupling constants and chemical shifts have been measured for arsenobetaine bromide and tetraphenylarsonium bromide. Similarly, (121/123)Sb NMR parameters have been measured for tetraphenylstibonium bromide and potassium hexahydroxoantimonate. The predicted pseudo-tetrahedral symmetry at arsenic and the known trigonal bipyramidal symmetry at antimony in their respective tetraphenyl-bromide "salts" are reflected in the measured (75)As and (121)Sb nuclear quadrupole coupling constants, CQ((75)As)=7.8MHz and CQ((121)Sb)=159MHz, respectively. Results of density functional theory quantum chemistry calculations for isolated molecules using ADF and first-principles calculations using CASTEP, a gauge-including projector augmented wave method to deal with the periodic nature of solids, are compared with experiment. Although the experiments can be time consuming, measurements of (75)As and (121)Sb NMR spectra (at 154 and 215MHz, respectively, i.e., at B0=21.14T) with linewidths in excess of 1MHz are feasible using uniform broadband excitation shaped pulse techniques (e.g., WURST and WURST-QCPMG).
authors: (a)Department of Chemistry, Gunning-Lemieux Chemistry Centre, University of Alberta, Edmonton, AB, Canada T6G 2G2.
authors: Alexandra
authors: A
authors: Faucher
authors: Department of Chemistry, University of Ottawa, Ottawa, ON, Canada K1N 6N5. Electronic address: Victor.Terskikh@nrc-cnrc.gc.ca.
authors: Victor V
authors: VV
authors: Terskikh
authors: (a)Department of Chemistry, Gunning-Lemieux Chemistry Centre, University of Alberta, Edmonton, AB, Canada T6G 2G2. Electronic address: roderick.wasylishen@ualberta.ca.
authors: Roderick E
authors: RE
authors: Wasylishen
keywords: ADF; Antimony; Arsenic; CASTEP; DFT; High-field NMR spectroscopy; Solid-state NMR