Magnetic properties and homogeneous distribution of Gd3+ ions in gadolinium molybdenum borate glass with high Gd2O3 content

The magnetic susceptibility and specific heat of 21.25Gd2O3–63.75MoO3–15B2O3 (mol%) glass showing the crystallization of ferroelastic β′-Gd2(MoO4)3 crystals are examined in the temperature range of T = 1.8–300 K to clarify magnetic and distribution states of Gd3+ ions. The magnetic susceptibility obeys the Curie–Weiss law, giving the effective magnetic moment of μeff = 7.87 μB and the Weiss constant of θ = −0.7 K. Any peak such as λ-type anomaly is not observed in the temperature dependence of specific heat in T = 1.8–5 K. It is suggested that Gd3+ ions in the glass with a high Gd2O3 content of 21.25 mol% are distributed homogeneously and randomly as paramagnetic ions down to T = 1.8 K without inducing any strong magnetic interaction. The present study suggests that glasses based on the MoO3–B2O3 system are good hosts for the homogeneous solubility of a large amount of rare-earth oxides.