Kondo volume collapse in frustrated antiferromagnet: The case of Ce₂Pd₂In

Ce2Pd2In (Mo2FeB2-type of crystal structure) with the ferromagnetic ground state based on Ce-4f(1) states exhibits two distinct phases of pressure-driven destruction of magnetic order. For pressures up to 3 GPa, a gradual buildup of Kondo interactions and of incommensurate spin-density wave are observed, while the ordering temperature remain in the range 4-5 K. A gradual but fast suppression of magnetism and formation of heavy fermion state (estimated Sommerfeld coefficient gamma exceeding 400 mJ mol(-1) K-1) could be placed into the context of pressure evolution of crystal lattice, in which all nearest neighbors in the basal plane converged to the same value, forming a frustrated triangular lattice.