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Updated: Oct 29, 2026

Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene
Published on: August 22, 2017
Hyperfine Constants and Nuclear Shieldings from the Microwave Spectra of FBO, ClBO, and FBS
1Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, V6T 1Z1, Canada
Abstract:
Rotational spectra of the unstable molecules FBO, ClBO, and FBS have been measured in the 8-26 GHz frequency range using a pulsed jet cavity Fourier transform microwave spectrometer. The samples were prepared by passing electric discharges through mixtures of O2/BF3, O2/BCl3, or OCS/BF3, respectively, entrained in Ne. Hyperfine structures in the observed transitions have been resolved and analyzed in terms of nuclear quadrupole, spin-rotation, and spin-spin interactions. The quadrupole and spin-rotation coupling constants have been used to show that the electronic environment surrounding the boron nucleus of all three species is very similar. The spin-rotation constants have been used to determine, for the first time, experimental average shieldings of the Cl, F, and B nuclei of these molecules. Ab initio values for the nuclear shielding parameters have been calculated for comparison. Copyright 1998 Academic Press.
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