Yu Yi, Xiao Bin, Eichel Rüdiger-A, Alekseev Evgeny V
School of Physics and Electronics Information, Gannan Normal University, Ganzhou, 341000, PR China.
Institute of Energy and Climate Research (IEK-6), Forschungszentrum Jülich, D-52428, Jülich, Germany.
Chemistry. 2025 Jan 14;31(3):e202403343. doi: 10.1002/chem.202403343. Epub 2024 Dec 10.
A series of four new thorium tungstates, ATh(WO) (A=Li, K, Rb, Cs), were synthesized using high-temperature solid-state method. Structural studies of the materials reveal distinct structural changes with underlying similarities influenced by the nature of A-site cations. LiTh(WO) exhibits a two-dimensional corrugated sheet structure stabilized by Li cations, crystallizing in P space group. KTh(WO) crystallizes in I4/a space group and exhibits a three-dimensional framework consisting of ThO antiprisms and WO tetrahedra. RbTh(WO) forms in C2/c space group, showcasing a framework with two-dimensional sheet structure. CsTh(WO) is isostructural to RbTh(WO) but displays increased interlayer spacing due to the larger ionic radius of Cs. Raman spectroscopy confirms the structural data, revealing distinct vibrational modes that correlate with tungsten coordination changes from WO in LiTh(WO) to WO in the CsTh(WO). This study demonstrates how variation of alkali metals affects the structural properties of thorium tungstates series, showing a morphotropic evolution as a factor of the ionic radii of the alkali metals.
采用高温固态法合成了一系列四种新型钍钨酸盐ATh(WO)（A = Li、K、Rb、Cs）。对这些材料的结构研究表明，受A位阳离子性质影响，结构有明显变化且存在潜在相似性。LiTh(WO)呈现出由Li阳离子稳定的二维波纹状片层结构，结晶于P空间群。KTh(WO)结晶于I4/a空间群，呈现出由ThO反棱柱和WO四面体组成的三维骨架结构。RbTh(WO)形成于C2/c空间群，展现出具有二维片层结构的骨架。CsTh(WO)与RbTh(WO)同构，但由于Cs的离子半径较大，层间距增大。拉曼光谱证实了结构数据，揭示了与钨配位变化相关的不同振动模式，从LiTh(WO)中的WO到CsTh(WO)中的WO。本研究展示了碱金属的变化如何影响钍钨酸盐系列的结构性质，表明作为碱金属离子半径因素的变晶演变。
