Atomic charges in RBa₂Cu₄O₈lattices, determined by comparison of experimental and calculated nuclear quadrupole interaction parameters

Abstract

Nuclear quadrupole interaction parameters have been determined for the rare-earth and copper sites of the RBa2Cu4O8 lattices (R = Sm, Y, Er) by 67Cu(67Zn) and 67Ga(67Zn) emission Mössbauer spectroscopy. The lattice electric field gradient tensors have been calculated for all sites of the above lattices using the point charge approximation. A comparison of the measured and calculated parameters has shown that in the RBa2Cu4O8 lattices holes are predominantly confined to the oxygen chain sublattices.