A layered vanadium arsenate network decorated with the directly coordinated organonitrogen ligands: [V 4O 7(HAsO 4) 2( o-phen) 2] ( o-phen= o-phenanthroline)

Abstract

A novel layered vanadium arsenate [V 4O 7(HAsO 4) 2( o-phen) 2] 1 ( o-phen= o-phenanthroline) was synthesized by the hydrothermal reaction of V 2O 5, ZnCl 2, Na 2HAsO 4·7H 2O, o-phenanthroline ( o-phen) and water. Its structure was determined by elemental analyses, ESR spectrum, XPS spectrum, TG analysis, IR spectrum and the single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic system, space group P2/ c, a=10.122(2) Å, b=9.867(2) Å, c=15.367(3) Å, β=102.83(3)°, V=1496.4(5) Å 3, Z=1, λ(Mo Kα)=0.71073 Å, ( R( F)=0.0397 for 3422 reflections). Data were collected on a Rigaku R-AXIS RAPID IP diffractometer at 293 K in the range of 2.06°< θ<27.48°. The title compound contains an unusual two-dimensional (2D) As–V–O layer with four-, six- and eight-membered rings. The chelating o-phen ligands project perpendicularly above and below the undulating layer. 1 represents the first example of 2D inorganic vanadium arsenate backbone grafted with the directly coordinated organic ligands. Furthermore, the 3D supermolecular architecture is formed by π– π stacking interactions of the o-phen groups between adjacent layers.