Understanding the complex structural features and phase changes in Na2Mg2(SO4)3: A combined single crystal and variable temperature powder diffraction and Raman spectroscopy study
作者:I.A. Trussov、L.L. Male、M.L. Sanjuan、A. Orera、P.R. Slater
DOI:10.1016/j.jssc.2019.02.014
日期:2019.4
this system. We show that room temperature Na2Mg2(SO4)3 can only be prepared by quenching from high temperature, with slow cooling leading to phase separation to give the previously unreported systems, Na2Mg(SO4)2 and Na2Mg3(SO4)4. We report the structures of quenched Na2Mg2(SO4)3 (monoclinic, P21 ), as well as Na2Mg(SO4)2 (triclinic, P1̅̅ ) and Na2Mg3(SO4)4 (orthorhombic, Pbca) , detailing their complex
混合金属硫酸钠在矿物学和最近由于对用于电池应用的含钠离子材料的关注引起了相当大的关注。据报道,Na 2 Mg 2(SO 4)3相在高温下会转变成朗贝氏体,这很有趣,因为通常仅当大型碱金属离子(例如K,Cs)采用朗贝氏体结构时, , 存在。尽管如此,这一阶段的室温结构仍然难以捉摸,因此在这项工作中,我们报告了对该系统的详细结构研究。我们表明室温下Na 2 Mg 2(SO 4)3只能通过从高温淬灭来制备,缓慢冷却导致相分离,得到以前未报告的体系Na 2 Mg(SO 4)2和Na 2 Mg 3(SO 4)4。我们报告了淬火的Na 2 Mg 2(SO 4)3(单斜晶系,P2个1个 )以及Na 2 Mg(SO 4)2(三斜晶系,P1个̅̅ )和Na 2 Mg 3(SO 4)4(斜方晶,百佳) ,详细说明其复杂的结构特征。此外,我们报告了通过可变温度XRD和拉曼研究对淬火的Na 2 Mg 2(SO 4