INVESTIGATION OF V-2+ IMPURITY CENTER IN KMGF3 AND KZNF3 BY V-51-ENDOR MEASUREMENTS

51V-ENDOR measurements for a substitutional V2+ impurity center in KMgF3 and KZnF3 have been made using a microwave frequency of 35 GHz. The spin-Hamiltonian parameters including higher order hyperfine interaction term U(S3I) have been determined as following values: A=−258.337±0.005 MHz, gIβN⁄h=(11.255±0.005)×10−4 MHz/G, U=0.110±0.005 MHz for KMgF3, and A=−259.157±0.005 MHz, gIβN⁄h=(11.260±0.005)×10−4 MHz/G, U=0.118±0.005 MHz for KZnF3. To interprete the parameter U, calculation for V2+ in a cubic octahedral crystalline field including the contribution from excited 2G term is carried out. Other parameters are also discussed. A new value for the nuclear magnetic moment of 51V nucleus is proposed. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.