Experimental and Theoretical Validation of Room Temperature Intrinsic Ferromagnetism in Cr3C2 Due to Interstitial Carbon Atoms

Ferromagnetism is explored in Cr 3 C 2 from microscopic to electronic levels and the spin coupling is attributed to the p electrons of the nearest‐neighbor carbon atoms around the Cr–C atomic interactions. By using the spin‐polarized density functional calculations, four models are formulated. The models reveal that the C atoms seated in tri‐prism I site can induce magnetic moments and the C vacancies can also take part in the induced magnetic moment. The p – d orbital interactions between C interstitial atom and Cr atom contribute to two asymmetric states of majority and minority spins and lead to weak magnetic moments. The C interstitial atoms and C vacancies in the crystal lattice of Cr 3 C 2 are observed by high‐resolution transmission electron microscopy and electron‐spin resonance (ESR) techniques. The magnetic properties of Cr 3 C 2 are investigated by a superconducting quantum interference device.