Neutron Diffraction Study of CuFeO2

Neutron diffraction study revealed that a powdered CuFeO 2 , a quasi-two-dimensional antiferromagnet on a triangular lattice (AFT), has two successive magnetic phase transitions at low temperatures. In the high-temperature phase below T N1 =16 K, it has a monoclinic magnetic unit cell with five spins in a layer (\(√7a×√7a×2{c}\), γ=141.78°). At T N2 =10 K, it shows a discontinuous transition and enters the low-temperature phase with an orthorhombic magnetic unit cell with four spins in a layer (\(√3a×2{a}×2{c}\)). In both magnetic structures, spins are collinear and parallel to the c axis.