resumo
A new vanadium(III) phosphate, Na3V(OH)(HPO4)(PO4), has been synthesized by using mild hydrothermal conditions under autogeneous pressure. This material represents a very rare example of sodium vanadium(III) phosphate with a chain structure. The crystal structure has been determined by refinement of powder X-ray diffraction data, starting from the atomic coordinates of an isotypic compound, Na3Al(OH)(HPO4)(PO4), which was obtained under high temperature and high pressure. The phase crystallizes in monoclinic space group C2/m (No. 12) with lattice parameters a = 15.423(9) angstrom, b = 7.280(0) angstrom, c = 7.070(9) angstrom, = 96.79(7)degrees, V = 788.3(9) angstrom(3), and Z = 4. The structure consists of one-dimensional chains composed of corner-sharing VO5(OH) octahedra running along the b direction. They are decorated by isolated PO4 and HPO4 tetrahedra sharing two of their corners with the ones of the vanadium octahedra. The interconnection between the chains is assured by three crystallographically distinct Na+ cations. Magnetic investigation confirms the 3+ oxidation state of the vanadium ions and reveals an antiferromagnetic arrangement between those ions through the chain.
palavras-chave
POWDER DIFFRACTION; MALEIC-ANHYDRIDE; CATALYSTS; OXIDATION; RELIABILITY; COMPLEXES; CRITERION; BUTANE
categoria
Chemistry
autores
Ferdov, S; Reis, MS; Lin, Z; Ferreira, RAS
nossos autores
Maria Rute de Amorim e Sá Ferreira André
Professor Catedrático
Zhi Lin
Investigador Principalagradecimentos
The authors are thankful for financial support from FCT, POCI2010, and FEDER. S.F. also thanks FCT (SFRH/BPD/23771/2005) for a grant. The authors thank FCT for the VSM equipment (REEQ/1126/2001).