A new compound Sr2FeWO6 has been synthesized by solid state sintering. The phase transition of this compound was investigated by means of differential scanning calorimetry (DSC), X-ray powder diffraction, precise meas...A new compound Sr2FeWO6 has been synthesized by solid state sintering. The phase transition of this compound was investigated by means of differential scanning calorimetry (DSC), X-ray powder diffraction, precise measurement of lattice parameters and other methods. It has been discovered that the compound has a displacive phase transition of the first order at (360±5)°. The low temperature phase, α-Sr2FeWO6, belongs to tetragonal crystal system, with space group I4/m; its lattice parameters at room temperature are: a=b=0.55702 nm, and c=0.79094 ran, the measured density is Dm = 6.93 g/cm3, and each unit cell contains two formula weights. The high temperature phase, β-Sr2FeWO6, belongs to the cubic system, with space group Fm3m and the lattice parameter is a=0.7939nm at 400°; z=4. The calculated density is Dx =6.780 g/cm3. The crystal structures of α-Sr2FeWO6 and β-Sr2FeWO6 were also determined by means of the X-ray polycrystal diffraction method. The phase transition mechanism and the temperature are investigated.展开更多
文摘A new compound Sr2FeWO6 has been synthesized by solid state sintering. The phase transition of this compound was investigated by means of differential scanning calorimetry (DSC), X-ray powder diffraction, precise measurement of lattice parameters and other methods. It has been discovered that the compound has a displacive phase transition of the first order at (360±5)°. The low temperature phase, α-Sr2FeWO6, belongs to tetragonal crystal system, with space group I4/m; its lattice parameters at room temperature are: a=b=0.55702 nm, and c=0.79094 ran, the measured density is Dm = 6.93 g/cm3, and each unit cell contains two formula weights. The high temperature phase, β-Sr2FeWO6, belongs to the cubic system, with space group Fm3m and the lattice parameter is a=0.7939nm at 400°; z=4. The calculated density is Dx =6.780 g/cm3. The crystal structures of α-Sr2FeWO6 and β-Sr2FeWO6 were also determined by means of the X-ray polycrystal diffraction method. The phase transition mechanism and the temperature are investigated.
