Abstract
To establish the powder X-ray data we have synthesized gallium selenide (Ga3Se4) using spec. pure elements gallium and selenium of purity >99.999% adopting three different methods as solid melts, quenching, and quenching-annealing. An optimized condition for the synthesis of these materials using evacuated and sealed ampoule has been established. The powder X-ray diffraction analysis revealed that Ga3Se4 can only grow at elevated temperature by quenching and long annealing at suitable temperature. The material prepared by quenching-annealing at 500 degrees C over 500 h was identified as single phased polycrystalline Ga3Se4, and crystallizes in the cubic cell with a(o) =5.4531 angstrom, v= 162.155 angstrom(3), D-x = 5.375 g/cm(3), Z = 1, parameter of atoms Z(Ga) = 3, Z(Se) =4 and space group F43m. The low values of dielectric constant and dielectric loss confirm that the specimen has very low density of defects. Negative dielectric constant has been found. (C) 2012 Elsevier GmbH. All rights reserved.