Variation of chemical shielding with intermolecular interactions and rovibrational motion. IV. 11B and 13C nuclei in BF3 and CH4

Abstract

The temperature dependence of chemical shielding of 11B and 13C in an isolated BF3 or CH4 molecule is found to be negligibly small. It mat be generally true that the chemical shielding of a nucleus located at the center of symmetry of a molecule changes very little with vibration and rotation. The second virial coefficients σ1 are reported for these systems, as well as the dependence of the 11B–19F coupling constant on temperature and density.