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用固态烧结法合成了新化合物Sr_2FeWO_6。用差示扫描量热法(DSC)、X射线物相分析及点阵常数的精确测定等方法研究了新化合物Sr_2FeWO_6的相变,证明该化合物在(360±5)℃存在一级位移型相变。低温相α-Sr_2FeWO_6,属四方晶系,空间群为I4/m,室温时点阵常数a=5.5702A,c=7.9094A。测量密度D_m=6.93g/cm~3,单位晶胞内具有2个化学式量。高温相β-Sr_2FeWO_6,属立方晶系,空间群为Fm3m,在400℃时的点阵常数a=7.939A,z=4。计算密度D=6.780g/cm~3。
A new compound Sr 2 FeWO 6 was synthesized by solid state sintering. The phase transition of the new compound Sr 2 FeWO 6 was studied by means of differential scanning calorimetry (DSC), X-ray phase analysis and exact determination of lattice constants. The results show that the compound has a first-order phase shift at (360 ± 5) ℃ change. Low-temperature phase α-Sr 2 FeWO 6, belongs to the tetragonal system, the space group is I 4 / m, the lattice constant at room temperature a = 5.5702A, c = 7.9094A. Measurement density D_m = 6.93g / cm ~ 3, unit cell with two chemical formula. The high-temperature phase β-Sr 2 FeWO 6 belongs to the cubic system with the space group Fm3m and the lattice constant a = 7.939A and z = 4 at 400 ℃. Calculate the density D = 6.780g / cm ~ 3.