摘要
不同浓度的Na2SO4水溶液的拉曼光谱显示了SO42-的四个拉曼活性带:980 cm-1处的SO42-的对称伸缩振动模式v1带,1 106 cm-1处的反对称伸缩振动模式v3带,448 cm-1处的变形振动模式v2带和617 cm-1处的变形振动模式v4带。482 cm-1处的肩膀峰是由于NaSO4-离子对的形成对448 cm-1的v2带的影响而形成的SO42-的一个新的振动峰。浓Na2SO4水溶液中,水共享离子对[Na+.H2O.SO42-]-是主要的离子对物种。随着Na2SO4水溶液浓度的增加,Na+和SO42-的相互作用增强,NaSO4-离子对所占的摩尔分数增加。
Raman spectra of concentrated aqueous Na2SO4 solutions were measured at room temperature. The Raman spectra manifest four Raman-active vibration modes for SO4^2-： the symmetric SO4^2- stretching mode v1 band at 980cm^- 1, the antisymmetric SO42- stretching mode v3 band at 1 106 cm^-1, depolarized deformation modes v2at 448 cm^-1 and V4 at 617cm^- 1. A shoulder at 482 cm^- 1 appearing beside the v2 band is inferred as a vibration of SO4^2- due to the influence of formation of NaSO^4- ion pairs on v2 vibration. Water sharing NaSO4-ion pairs are dominating ion - pair speciesin concentrated aqueous Na2SO4 solutions. Interaction between Na^ ＋ and SO4^2- strengthens and molar fraction of NaSO^4- ionic pair increases, with increasing concentration of aqueous Na2SO4 solutions.
出处
《盐湖研究》
CSCD
2005年第4期42-46,共5页
Journal of Salt Lake Research
