Hyperfine interaction and chemical bonding in the PdH molecule
Knight, L. B.; Weltner, W. Hyperfine interaction and chemical bonding in the PdH molecule. J. Mol. Spectrosc. 1971, 40, 317-327.
The ESR spectra of PdH and PdD molecules in the 2Î£+ ground state have been observed while trapped in argon (and krypton) matrices at 4Â°K. The hyperfine coupling tensor components relative to both 105Pd and H or D nuclei were determined and g tensor components found to be gâ€– = 1.965, gâŠ¥ = 2.293. Analysis of these data indicate that the ground-state configuration of PdH is KLMNsp (4dÎ´)4(4dÏ€)4(5sÏƒ)2(4dÏƒ) and that an excited 2Î i state of configuration â‹¯(4dÏ€)3(5Ïƒs)2(4dÏƒ)2 lies about 20,000 cmâˆ’1 above the X2Î£. The value of gâŠ¥ is in accord with this and also in accord with the observed large negative value of Î³0, the spin-doubling constant in the ground state. The spin density on H is small (probably <10%) indicating that the bonding is highly ionic.
Journal of Molecular Spectroscopy