NUCLEAR MAGNETIC RESONANCE OF CD IN CDCR2SE4 AND CDCR2S4 AND TRANSFERRED SPIN POLARIZATION IN CHROMIUM CHALCOGENIDE SPINELS

Purely isotropic hyperfine fields have been observed for Cd111 and Cd113 by zero-field NMR in both ferro-magnetic CdCr2Se4 and CdCr2S4. The values at 4.2 K are + 136.20.2 and (+) 167.00.2 kOe, respectively. Combined with earlier results for Cr53 and Se77 in CdCr2Se4, this work allows estimates to be made of the amount of unpaired spin covalently transferred to the nonmagnetic ions. Transfers between ligands and the 4s level of Cr3+ are particularly important. Some consequences for the magnetic properties of the system are discussed. © 1969 The American Physical Society.