摘要
通过一系列电解质体系水的拉曼光谱测量，得到了阴、阳离子种类和浓度引起的水伸缩振动和弯曲振动谱带丰富的变化信息．ClO4－能有效地破坏水分子间的氢键，随着ClO4－浓度的增加，水分子间的氢键并非逐步被打断，而是氢键被破坏的水分子越来越多，从而使水分子有序度增大，这种氢键破坏方式符合水的混合模型（MixtureModel）．SO42－浓度的增加对水的Raman光谱影响较小，是由于SO42－与水分子间有氢键作用的结果．虽然阳离子浓度对水的Raman光谱影响很小，但不同阳离子体系水的Raman谱有较大的差别，Li十与Cs十会引起水分子的拉曼谱较大的变化，Na十与K十对水的拉曼谱影响都不大．
Raman spectra of aqueous solutions contatheng ClO4- SO42- , Li+, Na+ , K+ , Cs+ were meastired. The effects of the concentrations and the properties of these ions on the frequencies, band shape and relative strength of the stretching and bending vibration bands of water molecules were compared in detail. With increasing the concentration of ClO4-, a typical stucture-breaking anion, the strengh of the O-H stretching vibration pealls at lower wavenUmber (3244 and 3396 cm-1) decreases and a new peak at higher wave nUmber (3552 cm-1) appears and is becodring the strongest one at the 8 mol.L-1 NaClO4 solution, this is obviously dtherent from the temperaure-dependent Raman spectra of pure water in that the O-H stretching vibration frequency continously shifts to higher wavenumber with increasing temperature, indicating that the process of hydrogen-bond breaking by ClO, between water molecules could be expressed by the Anxture model.For SO42- however, the concentration effect on the Rarnan spectra of water is very weak because SO42- is a stIUCture-making anion which can form hydrogen bond with water molecules. It has been also found that Li+ and Cs+ have siInjlar effects on the Raman spectra of water, while the effects of Na+ and K+ are very weak.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
1996年第2期130-135,共6页
Acta Physico-Chimica Sinica
基金
国家自然科学基金
北京理工大学人才基金
关键词
散射谱
水
氢键
电解质体系
Raman spectroscopy, Water, Hydrogen-bond
