Abstract
AbstractThe ESR spectra of Cr doped PbMoO4 originate from CrO ions at normal MoVI sites with a d ground state interacting with 207Pb nuclei of two sets of four first‐neighbour lead sites. The principal values and the directions of the principal axes of the two Cr5+−Pb2+ hf tensors are determined and discussed according to the nature of the cation—cation interactions. The temperature dependence of the spectrum intensity, which falls to zero outside the 10 to 45 K region is explained as a combination of a very short Cr5+ spin lattice relaxation time and a long spin diffusion time. The yellow coloration of oxidized samples of PbMoO4 (Cr) results from the existence of an intense line (f = 0.14) in its absorption spectrum peaking at 430 nm. This band is attributed to a charge transfer transition of CrO ions which is red shifted from its normal position in most chromates because of a mixing with a Pb2+ → Cr6+ intervalence transition.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call