Etude par corrélation angulaire γ-γ perturbée des interactions moléculaires du chelate Hf (C₇H₅O₂)₄ avec le chloroforme et la N,N-diméthylformamide à l'état solide

Hyperfine quadrupole coupling and .pi. bonding in dodecahedral chelates of hafnium(IV)

“…Relativistic calculations performed by Desclaux32 for Ta2+, Ta3+, and Ta4+ free-ion configurations show that the weightaverage quantity (r~3)sp3d't is a smoothly varying function of the net charge on the central atom. For the Ta3+ configuration, the following values are obtained: (r~3)5d = 8.1 au, ( •"3)6 = 12 au, (f-3)sp3d4 (r~3)h = 7.5 au. According to the more recent calculations of core polarization effects,33,34 values of 0.15 and -64 are reasonably expected for R and ", respectively.…”