We experimentally investigate effects of W⁶⁺ occupying the sites of Sc³⁺ in the unit cell of Sc₂W₃O₁₂ (Sc₈W₁₂O₄₈) on the structure, vibration and thermal expansion. The composition and structure of the doped sample (Sc₆W₂)W₁₂O_{48 δ} (with two W⁶⁺ occupying two sites of Sc³⁺ in the unit cell of Sc₈W₁₂O₄₈) are analyzed and identified by combining the x-ray photoelectron spectroscopy and the synchronous x-ray diffraction with first-principles calculations based on density functional theory. Results show that the crystal with even W⁶⁺ occupying even Sc³⁺ in the unit cell is stable and maintains the orthorhombic structure at room temperature. The structure of the doped sample is similar to that of Sc₂W₃O₁₂, and with even W occupying even positions of Sc in the unit cell and constituting the WO₆ octahedra. Raman analyses show that the doped sample possesses stronger W–O bonds and wider Raman linewidths than those of Sc₂W₃O₁₂. The sample doped with W also exhibits intrinsic negative thermal expansion in the measured range of 150 K–650 K.

我们通过实验研究了W ⁶⁺占据Sc ₂ W ₃ O ₁₂ (Sc ₈ W ₁₂ O ₄₈ )晶胞中Sc ³⁺的位置对结构、振动和热膨胀的影响。_{掺杂样品(Sc 6} W ₂ )W ₁₂ O _{48 δ}的组成和结构(两个W ^6+在Sc ₈ W ₁₂ O ₄₈的晶胞中占据两个Sc ^3+位点 ) 通过结合 x 射线光电子能谱和同步 x 射线衍射与基于密度泛函理论的第一性原理计算进行分析和识别。结果表明，在晶胞中偶数W ⁶⁺占据偶数Sc ³⁺的晶体是稳定的，在室温下保持正交结构。掺杂样品的结构与Sc ₂ W ₃ O ₁₂相似，偶W在晶胞中占据Sc的偶数位置，构成WO ₆八面体。拉曼分析表明，掺杂样品比 Sc ₂ W ₃ O具有更强的 W-O 键和更宽的拉曼线宽。₁₂ . 掺杂 W 的样品在 150 K-650 K 的测量范围内也表现出固有的负热膨胀。