Charge Distribution and Hyperfine Interactions in the CuFeO2 Multiferroic According to 63,65Cu NMR Data

Abstract

For the first time, the CuFeO₂ single crystal has been studied by ^63,65Cu nuclear magnetic resonance (NMR). The measurements have been carried out in the temperature range of T = 100−350 K in the magnetic field H = 117 kOe applied along different crystallographic directions. The components of the electric field gradient tensor and the hyperfine coupling constants are determined. It is shown that electrons of copper 4s and 3d orbitals are involved in the spin polarization transfer Fe → Cu. The occupancies of these orbitals are estimated.