摘要
用径向分布函数(RDF)法、喇曼光谱和红外光谱研究了在Li_2OP_2O_5系统玻璃中引入Ba^(2+)离子取代Li^+离子对玻璃结构的影响。测试表明,含钡锂磷酸盐玻璃的主要结构为以[P0_4]为单元的链状网络结构。RDF曲线可以提供关于Ba^(2+)离子分布的重要信息。RDF曲线上的4.00—4.15A和7.15—7.45A特征峰位表示Ba-Ba近邻距离。键角ф_(o-p-o)和力常数F_(m-o)的错综变化,在喇曼光谱上表现为玻璃主要结构(如[PO_4]链)特征峰的波数和强度发生微小的变化。玻璃中B^(2+)离子的存在使连接非桥氧的方向键有所加强,将影响磷酸盐链之间离子键的强度,从而导致玻璃的一些物理性质的变化。
The structural effects of substituting Ba^(2+) ions for Li^+ ions in Li_2O-
P_2O_5 glasses have been investigated by Readial distribution function
(RDF) method, Raman spectroscopy and IR spectroscopy. The results
of the Raman experiments and IR experiments on Li_2O-P_2O_5 glasses in
whith Ba^(2+) ions have been substituted for Li^+ ions show that the
major glass structurc consists primarily of chains of corner sharing
PO_4 tetrahedra. RDF curves of glasses containing barium and lithium
atoms can provide significant information about the distribution of Ba^((?)+)
ions. The spectral peaks in the 4.00-4.15A and 7.15-7.45A are thought
to arise primarily from Ba-Ba distance. Subtle changes in(PO_2) bond
angle φo_P_o and the iorie bond force constant of the nonbridging oxygens
F_(m_o). are manifested in the observed spectra as slight chaages in vibra-
tional frecuencies and relative intensities of the bands characteristic of the
major glass structural species, the PO_4 chains. The presence of Ba^((?)+)
ions of the glasses results in some increase in the directional bonding
of the nonbridging oxygens, which would affect the strength of the ionic
bonding between the phosphate chains. This effect could be resposible for
the variation of physical properties.
关键词
玻璃
光谱
玻璃结构
Glass
Experiments
Structure
