Brázdová Veronika, Ganduglia-Pirovano M Verónica, Sauer Joachim
Humboldt Universität zu Berlin, Institut für Chemie, Unter den Linden 6, D-10099 Berlin, Germany.
J Phys Chem B. 2005 Jan 13;109(1):394-400. doi: 10.1021/jp046055v.
We present periodic density functional calculations within the generalized gradient approximation (Perdew-Wang 91) on structure and vibrational properties of bulk AlVO(4). The optimized structure agrees well with crystallographic data obtained by Rietveld refinement (the mean absolute deviation of bond distances is 0.032 A), but the deviations are larger for the lighter oxygen atoms than for the heavier Al and V atoms. All observed bands in the Raman and IR spectrum have been assigned to calculated harmonic frequencies. Bands in the 1020-900 cm(-1) region have been assigned to V-O((2)) stretches in V-O((2))-Al bonds. The individual bands do not arise from vibrations of only one bond, not even from vibrations of several bonds of one VO(4) tetrahedron. The results confirm that vibrations around 940 cm(-1) observed for vanadia particles supported on thin alumina film are V-O-Al interface modes with 2-fold coordinated oxygen atoms in the V-O((2))-Al interface bonds.
我们采用广义梯度近似（Perdew-Wang 91）下的周期性密度泛函计算方法，研究了块状AlVO₄的结构和振动性质。优化后的结构与通过Rietveld精修获得的晶体学数据吻合良好（键长的平均绝对偏差为0.032 Å），但较轻的氧原子的偏差比重的铝和钒原子的偏差更大。拉曼光谱和红外光谱中观察到的所有谱带都已与计算得到的简正频率相对应。1020 - 900 cm⁻¹区域的谱带已被指定为V - O₂ - Al键中V - O₂的伸缩振动。各个谱带并非仅源于一个键的振动，甚至也不是源于一个VO₄四面体中几个键的振动。结果证实，在薄氧化铝膜负载的氧化钒颗粒中观察到的940 cm⁻¹附近的振动是V - O - Al界面模式，其中V - O₂ - Al界面键中的氧原子具有2重配位。
