水和重水红外吸收光谱的Car-Parrinello分子动力学模拟  

Infrared absorption spectra of liquid water and deuterated water by Car-Parrinello molecular dynamics

作　　者：王程超 谭建宇 杨家跃 刘林华[1,2] 

机构地区：[1]哈尔演下业大学威海汽车工程学院,威海264209 [2]哈尔滨工业大学能源科学与工程学院,哈尔滨150001

出　　处：《科学通报》2015年第31期3014-3020,共7页Chinese Science Bulletin

基　　金：国家自然科学基金重点项目(51336002);教育部新世纪人才基金(NCET-12-0152)资助

摘　　要：红外吸收光谱在水的热力学及动力学特性研究中起到了关键作用.本文采用基于密度泛函理论的Car-Parrinello分子动力学(CPMD)方法研究了水和重水的红外吸收性质及介电和光学特性.以能量最小化构型为输入结构,运用该方法计算室温下水和重水的分子电偶极矩总和,进而通过傅里叶变换得到红外吸收光谱.数值分析表明:室温下水和重水红外吸收光谱的理论计算值与文献中实验结果相吻合,表征OH键拉伸模式的光谱峰值位置略有红移,验证了CPMD方法的可行性,为高温高压等极端工况下水的基础物性参数研究提供了参考.Infrared （IR） absorption spectra plays a key role in the study of thermodynamic and dynamic properties of liquid water. Car-Parrinello molecular dynamics simulations within the framework of density-functional theory are used to study the IR absorption, dielectric function and optical properties of liquid water and deuterated water. Using the energy minimization model to obtain the input structure, we calculate the molecular dipole moment of water and deuterated water at ambient temperature, and then obtain the IR absorption spectra by Fourier transforming the autocorrelated function of dipole moment. As the numerical analysis indicates, the calculated results fit well with previous literature experiments. The absorption peak represents the stretching mode of oxygen-hydrogen covalent bond and shows a slight red shift. The dielectric functions and optical constants of water and deuterated water at the temperature of 303 K are extracted from IR absorption spectrum.

关 键 词：红外吸收光谱 光学常数 CPMD 第一性原理 

分 类 号：O433.51[机械工程—光学工程]