Local structures of liquid and vitreous V2O5 and P2O5

Neutron and X-ray diffraction measurements were carried out for liquid and vitreous V2O5 to make clear the detailed atomic structure. A first sharp di ffraction peak is observed around 0.5 Angstrom(-1) in the structure factor of vitreous V2O5. VO4 tetrahedral unit exists dominantly in the liquid stat e and those units are connected to each other by sharing the three corner-s ite O atoms of four. The VO4 tetrahedral unit is distorted in vitreous V2O5 . Neutron diffraction of P2O5 suggests that the local structures of liquid and vitreous P2O5 are also based on PO4 tetrahedral unit similar to that of V2O5. (C) 1999 Elsevier Science Ltd. All rights reserved.