Vibrational spectra and structure of alkali germanate glasses
Vibrational spectra and structure of alkali germanate glasses
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DOI：
10.1016/s0022-3093(01)00690-1
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发表时间：
2001-11-01
影响因子：
3.5
通讯作者：
Almeida, RM
中科院分区：
文献类型：
--
作者：
Di Martino, D;Santos, LF;Almeida, RM
到目前为止，已经进行了许多结构研究，以阐明所谓锗异常的性质，但正确的结构模式仍不清楚。本论文的目的是进一步阐明碱性锗酸盐玻璃的结构，即含有钠和铯氧化物的玻璃。制备了两个系列的玻璃样品，其摩尔组成为(100-x)GeO2。XM(2)O(M=Na且0小于或等于x小于或等于35，或M=Cs且0小于或等于x小于或等于25)。记录了这些玻璃的偏振拉曼光谱和红外吸收光谱，作为碱含量的函数；还进行了红外反射率测量，并将近垂直入射光谱的Kramers-Kronig分析与玻璃的偏振拉曼光谱进行了比较。一幅整体的结构图已经出现，这与少数较高配位的Ge原子的存在是一致的，无论是五重还是六重。(C)2001 Elsevier Science B.V.保留所有权利。
Numerous structural studies have been carried out so far to elucidate the nature of the so-called germanate anomaly but the correct structural model is still unknown. The objective of the present paper is to shed further light on the structure of alkali germanate glasses, namely those containing sodium and cesium oxides. Two series of glass samples were prepared, having molar compositions (100 - x)GeO2 . xM(2)O (M = Na and 0 less than or equal to x less than or equal to 35, or M = Cs and 0 less than or equal to x less than or equal to 25). Polarized Raman and infrared absorption spectra were recorded for these glasses, as a function of the alkali content; infrared reflectivity measurements were also carried out and Kramers - Kronig analysis of the near-normal incidence spectra were compared with the polarized Raman spectra of the glasses. An overall Structural Picture has emerged, which is compatible with the presence of a fraction of higher coordinated Ge atoms, either five-fold or six-fold. (C) 2001 Elsevier Science B.V. All rights reserved.