Modelling IR-spectra of single-phase polycrystalline materials with random orientation – Supplementations and refinements for optically uniaxial crystallites
Modelling IR-spectra of single-phase polycrystalline materials with random orientation – Supplementations and refinements for optically uniaxial crystallites
复制标题
随机取向单相多晶材料的红外光谱建模 – 光学单轴微晶的补充和改进
DOI：
10.1078/0030-4026-00275
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发表时间：
2003
期刊：
影响因子：
3.1
通讯作者：
T. Höche
中科院分区：
文献类型：
--
作者：
T. Mayerhöfer;Z. Shen;R. Keding;T. Höche
摘要 给出了随机取向的多晶镁锰矿 (Ba2TiSi2O8) 块状样品的红外反射光谱。该样品是通过火花等离子烧结由光学大微晶组成的粉末制备的。光谱的质量明显高于传统制备的样品的质量，尤其是交叉偏振项的光谱。光谱通过 4 × 4 矩阵形式建模 [T. G. Mayerhofer，J. Opt。答：纯应用。选择。 4, 540 (2002)]，针对光学单轴晶体进行了改进，从而正确预测了交叉偏振项的相对峰值强度。使用两种不同的方向平均方案进行建模。建模光谱和测量光谱之间的比较表明，在固体红外光学性质的定向平均的情况下，使用任何权重因子都是不合理的。
Summary The IR-reflectance spectra of a bulk sample of randomly oriented polycrystalline fresnoite (Ba2TiSi2O8) are presented. The sample was prepared by Spark Plasma Sintering from a powder consisting of optically large crystallites. The spectra are of notable higher quality than those of conventionally prepared samples, especially those of the cross-polarization terms. The spectra were modelled by a 4 ×4-matrix-formalism [T. G. Mayerhofer, J. Opt. A: Pure Appl. Opt. 4, 540 (2002)], which was refined for optically uniaxial crystals, resulting in a correct prediction of the relative peak-intensities of the cross-polarization terms. The modelling was carried out with two different orientational averaging schemes. The comparison between modelled and measured spectra revealed that the use of any weighing factor is unjustified in case of orientational averaging of the IR-optical properties of solids.