Sm2NiSn4: The intermediate structure type between ZrSi2 and CeNiSi2

A new rare earth nickel stannide, Sm2NiSn4, has been prepared by reacting the pure elements at high temperature in welded tantalum tubes. Its crystal structure was established by single crystal X-ray diffraction studies. Sm2NiSn4 crystallizes in the orthorhombic space group Pnma (No. 62) with cell parameters of a=16.878(2) Å, b=4.4490(7) Å, c=8.915(1) Å, and Z=4. Its structure can be viewed as the intermediate type between ZrSi2 and CeNiSi2. Sm2NiSn4 features two-dimensional (2D) corrugated [NiSn4]6− layers in which the 1D Sn zigzag chains and the 2D Sn square sheets are bridged by Ni atoms. The Sm3+ cations are located at the interlayer space. Results of both resistivity measurements and extended-Hückel tight-binding band structure calculations indicate that Sm2NiSn4 is metallic.

Graphical AbstractA new rare earth nickel stannide, Sm2NiSn4, has been prepared by the solid-state reactions of the corresponding pure elements at high temperature in welded tantalum tubes. Its structure can be viewed as the intermediate type between ZrSi2 and CeNiSi2. Sm2NiSn4 features 2D corrugated [NiSn4]6− layers in which the 1D Sn zigzag chains and the 2D Sn square sheets are bridged by Ni atoms. Results of both resistivity measurements and extended-Hückel tight-binding band structure calculations indicate that Sm2NiSn4 is metallic.Figure optionsDownload full-size imageDownload as PowerPoint slide