High-Pressure Phase Relations and Crystal Structures of Postspinel Phases in MgV<sub>2</sub>O<sub>4</sub>, FeV<sub>2</sub>O<sub>4</sub>, and MnCr<sub>2</sub>O<sub>4</sub>: Crystal Chemistry of AB<sub>2</sub>O<sub>4</sub> Postspinel Compounds
作者:Takayuki Ishii、Tsubasa Sakai、Hiroshi Kojitani、Daisuke Mori、Yoshiyuki Inaguma、Yoshitaka Matsushita、Kazunari Yamaura、Masaki Akaogi
DOI:10.1021/acs.inorgchem.8b00810
日期:2018.6.4
high-pressure, high-temperature phase transitions of spinel (Sp)-type MgV2O4, FeV2O4, and MnCr2O4. At 1200–1800 °C, MgV2O4 Sp decomposes at 4–7 GPa into a phase assemblage of MgO periclase + corundum (Cor)-type V2O3, and they react at 10–15 GPa to form a phase with a calcium titanite (CT)-type structure. FeV2O4 Sp transforms to CT-type FeV2O4 at 12 GPa via decomposition phases of FeO wüstite + Cor-type V2O3
我们研究了尖晶石(Sp)型MgV 2 O 4,FeV 2 O 4和MnCr 2 O 4的高压高温相变。在1200–1800°C下,MgV 2 O 4 Sp在4–7 GPa处分解为MgO周长石+刚玉(Cor)型V 2 O 3的相组装,它们在10–15 GPa下反应形成与钛酸钙(CT)型结构。FeV 2 O 4 Sp通过FeO辉石+ Cor型V 2 O 3的分解相转变为12 GPa的CT型FeV 2 O 4。。MnCr 2 O 4 Sp在10 GPa和1000–1400°C下直接转变为铁酸钙(CF)结构相。CT型MgV 2 O 4和FeV 2 O 4以及CF型MnCr 2 O 4的Rietveld改进证实,CT型和CF型结构均具有由边缘共享的B 3+ O 6八面体的双链形成的骨架(B 3+= V 3+和Cr 3+)平行于正交晶胞轴之一延伸。相对较大的A 2+阳离子(A 2+ = Mg 2 +,Fe