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Structural studies of Sr2GaSbO6, Sr2NiMoO6, and Sr2FeNbO6using pressure and temperature

“…Further evidence for this observation is provided by the three compounds that are the focus of this study, Sr 2 NiMoO 6 , Sr 2 GaSbO 6 , and Sr 2 FeNbO 6 , as each one has been described with several different unit cell symmetries. At ambient pressure and temperature Sr 2 NiMoO 6 has been reported to be tetragonal with a ≈ c ≈ 3.93 Å [14], tetragonal with a ≈ 7.84 Å and c ≈ 7.90 Å [15,16], and tetragonal with a ≈ 5.55 Å and c ≈ 7.89 Å [17,18]. At ambient pressure and temperature, the lattice of Sr 2 GaSbO 6 has been reported to be cubic with a ≈ 7.9 Å [19], tetragonal with a ≈ c ≈ 7.9 Å [20], and more recently the structure was reported to crystallize in space group I 4/m (No 87) [21] with a ≈ 5.5 Å and c ≈ 7.9 Å [22].…”

Magnetic Ordering and Structural Transition in the Ordered Double-Perovskite Pb2NiMoO6

“…Next, we focus on the electrical transport property of PNMO. Figure shows the temperature dependence of resistivity for the PNMO sample, which exhibits semiconducting behavior same as Sr 2 NiMoO 6 . The resistivity of PNMO is about 1.67 × 10 5 Ω cm at 300 K. The inset presents the linear fit to the curve of ln­(ρ) as a function of inverse temperature using the formula of ρ ∝ exp­(Δ g /2 k B T ), where Δ g is the semiconducting band gap and k B is the Boltzmann constant.…”