“…6 On the other hand, layered superconductors often proclaim new physics, such as p-wave spin-triplet superconductor Sr 2 RuO 4 . 7 In recent years, the antiperovskite carbides AXM 3 (X, carbon, boron or nitrogen; M, transition metal) have attracted considerable attention due to lots of interesting properties, such as superconductivity, 8,9 non-Fermi liquid behavior, 10 strong electron-electron correlation, 11 giant magnetoresistance (MR), 12,13 large negative magnetocaloric effect (MCE), 14,15 giant negative thermal expansion, 16,17 magnetostriction, 18 and nearly zero temperature coefficient of resistivity. 19 Specially, in MgCNi 3 despite the strong expectation for ferromagnetism due to full occupancy of Ni, it shows superconductivity with a T C about 8 K. 8 Experiments and energy band calculations show that there is a van Hove singularity in the density of states (DOS) just below Fermi level (E F ), which leads to a large DOS at the E F (N(E F )), dominated by Ni-3d states.…”