Crystal structure and electronic state of the disordered S=1 system (LixV1-x)(3)BO5 with x similar or equal to 0.3

The crystal structure and electronic state of the (LixV1-x)(3)BO5 system wi th x similar or equal to 0.3 have been explored through measurements of the X-ray four-circle diffraction, electron transport, and magnetization, The crystal data at 297 K show an orthorhombic structure with space group Pbam; a = 9.195(1) Angstrom, b = 12.209(1) Angstrom, c = 2.9922(9) Angstrom, and Z = 4, The structure determined with the residual factors of R = 0.017 and R-w = 0.018 for 1048 independent reflections is of a ludwigite type; Li an d V atoms are located at the centers of an octahedron of oxygens with mixed occupancy, and the B atom resides in the middle of the oxygen triangles. T he V-V bonded linear trimer may exist there. The variable-range-hopping-lik e transport and the transition from a localized state with S similar or equ al to 1 to a spin-glass-like state are revealed, which are basically consis tent with the structural aspect. (C) 1998 Academic Press.