Hyperfine Interaction and Chemical Bonding in MgF, CaF, SrF, and BaF molecules
Knight, L. B. Hyperfine Interaction and Chemical Bonding in MgF, CaF, SrF, and BaF molecules. J. Chem. Phys. 1971, 54, 322-322.
ESRspectra of MgH, CaH, SrH, and BaH molecules in their ground 2 Î£ + states were measured while isolated in solid argon matrices at 4Â°K. The molecules were prepared by quenching metal and hydrogen atom beams in a stream of argon. g tensors and hyperfine structure (hfs) constants for interaction with H, and in the case of MgH, with 25Mg and D, were determined. For 25MgH, |â€‰Î¨ (0)â€‰| 2 at Mg and H nuclei were found to be 0.800(8) and 0.0663(2) a.u., respectively, in good agreement with 0.7635 and 0.03789 a.u. recently calculated by Chan and Davidson using a 953 CI wavefunction. It is evident that such elaborate calculations are necessary to obtain accurate theoretical spin densities. Hydrogen hf interaction within the group of molecules indicate less ionicity than in the corresponding diatomic fluorides although the spin density is still predominantly on the metal atoms. Metal p and d contributions are approximately derived from the observed Î”gâŠ¥ values and discussed in relation to the unitedâ€atom model.
Journal of Chemical Physics