13C and 1H nuclear magnetic shielding and spin–spin coupling constants of 13C-enriched iodomethane in gaseous mixtures with SF6 and CO2

13C and 1H NMR spectral parameters have been investigated for 13C-enriched iodomethane (13CH3I) in the gas phase. The solute compound was observed at low constant pressure (approx. 80 Torr) and the temperature of 300 K while sulfur hexafluoride and carbon dioxide were used as the gaseous solvents. It was found that the 13C and 1H chemical shifts of 13CH3I were linearly dependent on the solvent density. Similar dependence was also detected for the one-bond coupling constant, 1J(CH). For the first time the 13C and 1H NMR parameters for an isolated 13CH3I molecule were obtained, together with the coefficients responsible for the solute-solvent molecular interactions. q 2004 Elsevier B.V. All rights reserved.