VANADIUM(IV) OXIDE NANOTUBES: CRYSTAL STRUCTURE OF THE LOW-DIMENSIONAL QUANTUM MAGNET Na2V3O7

摘要

Fibers of Na2V3O7 have been obtained by solid state reaction. This compound crystallizes in the trigonal system, space group P31c, with a=10.886(1) angstroms, b=9.5380(1) angstroms, V=978.87(2), Z=6, and rho=3.163 g cm-1. The structure is built up by VO5 square pyramids connected via edges and apices to form fascinating vanadium(IV)-oxide nanotubes. The cohesion of the network is ensured by the Na atoms which are located around the nanotubes. The inner diameter of the nanotube is close to 5 angstroms, which can accommodate the presence of a Na atom Na1 inside the nanotube. Such geometry with all the V atoms in the valence state IV should give interesting ionic conductivity and magnetic properties. 20 refs.