Disparity between the transient hyperfine fields for Pt and Os in Fe; an electron vacancy sharing interpretation

Precessions of the 2 ₁ ⁺ states in¹⁹⁸Pt and¹⁹²Os have been measured in the enhanced transient hyperfine magnetic field acting on these nuclei as they recoiled through thin polarized cobalt foils. Two separate targets consisting of contiguous layers of¹⁹⁸Pt and¹⁹²Os electrodeposited on ～1 μm and ～4 μm Co foils were employed. The levels of interest were Coulomb excited by 80 MeV³²S and 220 MeV⁵⁸Ni beams and the precessions of the 2 ₁ ⁺ →0 ₁ ⁺ γ-ray angular distributions in both nuclides were measured simultaneously. The results of these studies are compared with recently reported similar studies in which ions of¹⁸⁸Os and¹⁹⁴Pt recoiled through thin polarized Fe foils. It is concluded that (i) the transient field acting on Pt in Fe is singularly anomalous, and (ii) the recent contention that the g-factors of the 2 ₁ ⁺ states in the event Pt isotopes may be substantially lower than had been reported in the literature cannot be sustained. This transient field discontinuity is examined in terms of possible molecular orbital electron vacancy sharing between Pt and Fe.