NONLINEAR MAGNETIC-SUSCEPTIBILITY OF SOME VANADATE GLASSES

The first measurements of the anomalous variation of d.c. magnetic susceptibility of the (50 - x) P2O5-xM-50V2O5 (M = Bi2O3 and Sb2O3, and x = O to 40 mol% M) oxide glasses around 20 to 30 mol% M are reported here. Similar anomalous behaviour was also observed in the electrical and other physical properties of the glasses (reported in the previous paper). Like electrical and dielectric properties, this anomaly in the magnetic properties was also found to be mostly associated with the anomalous variation of the V4+/V5+ ratio (around 20 to 30 mol% M) with the concentration of M. From the temperature (80 to 300 K)-dependent magnetic susceptibility data the V4+ ion concentrations have also been calculated, which agree quite well with those obtained from chemical analysis, and the small discrepancy is attributed to the presence of V3+ and/or V2+ ions in the glass.