Abstract We report on the magnetic properties of isostructural oxides R6AO12 (R = a rare-earth element, A = Mo or W) with high concentrations of rare-earth elements. We measured the magnetization and specific heat. Tm6MoO12 is a van Vleck paramagnet with a nonmagnetic singlet ground state (GS). Ho6WO12 exhibits an antiferromagnetic long-range order (AFM LRO) lower than T N = 2.1 K and its GS is a magnetic quasi-doublet. Dy6WO12 shows an AFM LRO lesser than T N = 2.7 K and its GS is a magnetic Kramers doublet. Er6MoO12 and Er6WO12 are Curie-Weiss paramagnets at temperatures above 2 K and both have a magnetic Kramers doublet GS. We evaluated the magnetic entropy change. The temperature of the maximum magnetic entropy change for a magnetic-field change of 5 T is high (15 K) in Tm6MoO12 in spite of an oxide containing only rare-earth ions as the magnetic ions.

中文翻译：

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含有高浓度稀土元素 R6AO12（R = 稀土元素，A = Mo 或 W）的氧化物的磁性

摘要 我们报告了具有高浓度稀土元素的同构氧化物 R6AO12（R = 稀土元素，A = Mo 或 W）的磁性。我们测量了磁化强度和比热。Tm6MoO12 是范弗莱克顺磁体，具有非磁性单线态基态 (GS)。Ho6WO12 表现出低于 TN = 2.1 K 的反铁磁长程有序 (AFM LRO)，其 GS 是磁性准双峰。Dy6WO12 显示 AFM LRO 小于 TN = 2.7 K，其 GS 是磁性克莱默双峰。Er6MoO12 和 Er6WO12 是温度高于 2 K 的居里-魏斯顺磁体，并且都具有磁性克莱默双峰 GS。我们评估了磁熵变。