腺嘌呤-水分子团簇结构与振动频率的理论研究  

Theoretical investigation of the structures and vibrational frequencies of adenine-water clusters

作　　者：陈文龙[1] 孔戈[1] 周留柱[1] 孔祥和[1] 

机构地区：[1]曲阜师范大学物理工程学院,曲阜273165

出　　处：《原子与分子物理学报》2016年第5期829-835,共7页Journal of Atomic and Molecular Physics

基　　金：曲阜师范大学科研启动基金(BSQD2004016);国家自然科学基金(11274200)

摘　　要：利用密度泛函理论在B3LYP/6-311＋＋G（d,p）基组水平上对C5H5N5·（H2O）m（m=13）进行了优化与振动频率计算,得到了团簇的六种稳定结构.应用AIM程序计算了三种最稳定结构的氢键临界点的拓扑参数,结果表明,O—H…N氢键的形成使得O—H之间电子密度减小,伸缩振动频率减小,产生了红移;N—H…O氢键的形成使得N—H之间的电子密度减小,键的强度变弱,伸缩振动频率变小,发生了红移.利用veda4软件对团簇C5H5N5·（H2O）m（m=03）的红外光谱的振动频率进行模式指认,并对部分振动频率进行了比较.The structures of C5H5N5·（ H2O）m（ m = 1 3） molecules were optimized and their vibrational frequencies were calculated using density functional theory（ DFT） at the B3 LYP /6-311 ＋ ＋ G（ d,f） level.AIM program was used to calculate the critical points’ topological parameters of three most stable structures.The results show that the strong red-shift of O—H…N hydrogen bond is attributed to the decreases of the O—H electron density and the stretching vibrational frequency,meanwhile the red-shift of N—H…O hydrogen bond is attributed to the decreases of the N—H electron density and the stretching vibrational frequency.The IR spectra of C5H5N5·（H2O）m（ m = 0 3） clusters were assigned by veda4 software and part of the vibration frequency were compared.

关 键 词：腺嘌呤 密度泛函理论 氢键 红外光谱 偶极矩 

分 类 号：O641[理学—物理化学]