论文标题
结构性属性和拉曼光谱columbite型ninb $ _ {2-x} $ v $ _x $ o $ $ _6 $在高压下合成
Structural properties and Raman spectra of columbite-type NiNb$_{2-x}$V$_x$O$_6$ synthesized under high pressure
论文作者
论文摘要
新的化合物ninb $ _ {2-x} $ v $ _x $ o $ $ _6 $（$ 0 \ leq x \ leq 2 $）的完整组合参数与不寻常的哥伦比特型结构。在包含钒的样品中，在高压和高温条件下的合成稳定了这种晶体结构。在这里，我们在这里报告NIV $ _2 $ o $ $ _6 $ - \ textsl {pbcn} polymorph的第一个拉曼光谱，并扩展了Ninb $ _2 $ o $ $ _6 $的先前观察到的模式的列表。还提出和讨论了沿该系列的Niobium取代钒时产生的振动拉曼光谱的演变。通过考虑到Niobium/Vanadium原子的局部结构环境的变化及其对周围镍氧键的影响来解释这种演变。钒原子的存在有利于在镍酮周围的氧原子排列中增加对称性。在对应物中，钒处于八面体环境中，比niobium更扭曲。由于这些显然微妙的差异，因此无法实现实心解决方案中钒的均匀分布。
The complete set of structural parameters of the new series of compounds NiNb$_{2-x}$V$_x$O$_6$ ($0\leq x \leq 2$) with the unusual columbite-type structure is presented here. In the samples containing vanadium, this crystalline structure was stabilized by synthesis in conditions of high pressure and high temperature. Here we report here the first Raman spectrum for the NiV$_2$O$_6$-\textsl{Pbcn} polymorph and extend the list of the previously observed modes for the NiNb$_2$O$_6$. The evolution of the vibrational Raman spectrum produced when the vanadium is substituted for niobium along the series is also presented and discussed. This evolution is interpreted by taking into account the changes in the local structural environment of the niobium/vanadium atoms and its influence over the nickel-oxygen bonds around them. The presence of vanadium atoms favors an increase of the symmetry in the arrangement of oxygen atoms around the nickel-ones; in counterpart, the vanadium is in an octahedral environment which is more distorted than that of the niobium. Because of these apparently subtle differences, the homogeneous distribution of vanadium in the solid solution NiNb$_{2-x}$V$_x$O$_6$ is not possible.
