NMR 63.65Cu in a Local Field and Relaxation of Nuclear Spins in a CuFeS2 Magnetic Semiconductor

The results of the study of the spectral and relaxation parameters of 63.65Cu nuclear magnetic resonance (NMR) in a local field in natural samples of the semiconductor mineral chalcopyrite (CuFeS2), which is characterized by a strong interplay of magnetic and electronic properties, are presented. The main attention was paid to the determination of the mechanism of nuclear spin–lattice relaxation. The well-resolved quadrupole structure of the 63.65Cu NMR spectrum allowed us to investigate the kinetics of nuclear magnetization recovery for both Cu isotopes. The magnetic mechanism of the spin–lattice relaxation of the nuclear spins of copper isotopes 63.65Cu in CuFeS2, due to fluctuations of the dipole local fields created by the electron spins of magnetic Fe3+ ions, has been determined.