Magnetic-properties of 2 new compounds - GD2NI3SI5 and SM2NI3SI5

The formation of two new materials, Sm2Ni3Si5 and Gd2Ni3Si5, of the rare‐earth series R2M3Si5 (R denotes rare earth and Y) and their magnetic and transport properties are reported here. These materials crystallize in the orthorhombic U2Co3Si5‐type structure (space group Ibam). The magnetic susceptibility of Gd2Ni3Si5 follows a Curie–Weiss behavior with an effective magnetic moment 8.1μB/Gd ion. The material orders antiferromagnetically at ≊15 K. The magnetic susceptibility of Sm2Ni3Si5 exhibits a deviation from the Curie–Weiss behavior which is attributed to the low‐lying excited state of Sm3+ ions and also to crystal‐field effects. This material also orders antiferromagnetically, but at ≊11 K. This value of the ordering temperature does not seem to follow the de Gennes scaling with respect to that of Gd2Ni3Si5.