Magnetic properties of EuSm₂S₄ and SrSm ₂S₄

Crystals of EuSm2S4 and SrSm2S4 having the cubic Th3P4 structure are insulators, with a random distribution of Sr2+ and Sm3+ over equivalent sites. EuSm2S4 is a ferromagnet with Tc=2.7 K. SrSm2S4 does not order magnetically above 1.4 K. A sharp upturn in its specific heat below 4 K is attributed to splitting of the Γ8 quartet by a small non-cubic crystal field.