Geometrical frustration in a new S = distorted check-board lattice PbCuTeO < inf > 5 < /inf >

Abstract

Geometrical frustration, arising from the unsatisfying magnetic bonds in peculiar magnetic materials, leads to the emergence of a variety of ground states ranging from exotic disordered (quantum spin liquid) to unusual magnetic ordered states. We have prepared and studied the magnetic properties of a novel quantum magnet PbCuTeO5, whose structure suggests that it has 2D distorted check-board lattice. A large antiferromagnetic Curie-Weiss temperature of -165 K and a spin freezing temperature Tf = 6 K are observed in the magnetic data. Our results suggest that PbCuTeO5 is a new frustrated quantum magnet with a large frustration parameter f = θCW/Tf > 27.