PHYSICAL PROPERTIES OF THE 1D MAGNET β- VOSO4

Abstract

In this work the β phase of Vanadiumoxosulphate (VI) (β −V OSO4) crystal was used to study the physical properties of low dimensional magnetism in spin ½ chains. Structural analysis from X-ray diffraction and neutron diffraction performed on the sample, confirm that it crystallizes in the Pnma (62) space group. β − V OSO4 has V4+ bounded to six oxygen that gives it an octahedral configuration with one unpaired electron, thus with a total spin 1/2. The V-O-V bound running parallel to the a-axis form a spin ½ chain. The physical effect of this spin chain on the magnetic susceptibility and heat capacity was examined and it shows that the magnetic moment is isotropic and the intra-chain magnetic interaction is antiferromagnetic. This magnetic behavior has a significant effect on the susceptibility and heat capacity at temperatures below 60K. The magnitude of the magnetic exchange interaction between the spins was calculated to range from 45.4(3) K to 43.9(5)K but from fits to the magnetic susceptibility curve the exchange interaction was model to be approximately 25.05(99)K in all direction. The magnetic contribution to the internal energy of the crystal was found to be approximately 4.5JK−1mol−1 at 50K