Anomalous low-temperature heat capacity in antiperovskite compounds

Guo Xin-Ge^{1, 2}, Lin Jian-Chao¹, Tong Peng^{1, †}, Lin Shuai¹, Yang Cheng¹, Lu Wen-Jian¹, Song Wen-Hai¹, Sun Yu-Ping^{1, 3, 4}

(color online) The structure of antiperovskite compound AXM ₃ for room temperature. Atoms A (transitional metals or semiconducting elements) occupy the cubic corner sites. Interstitial atom X (C, N) is at the body-centered position and transitional metals X atoms (Fe, Co, Mn) occupy the face-centered sites. The X and M atoms form an XM ₆ octahedron.