Spectroscopic Studies of Structures and Defect Activities ofIcy Clusters and Thin Films

德夫林教授得到了实验物理化学计划的资助，该计划利用红外光谱研究冰薄膜和冰团，包括结晶冰、无定形冰和酸性水合物。所获得的数据将加深我们对自然过程的理解，例如大气中冰粒的成核和生长，在电暴中导致电荷分离的冰面上的分子水平过程，以及生物膜-水界面上和沿线的质子传导性。在冰I、无定形冰、酸性水合物和笼状水合物的冰薄膜和团簇中，考察表面、界面和强近红外辐射对氢键固体的点缺陷活性(离子：氢和羟基离子，取向：L和D)的影响。傅立叶变换红外光谱和拉曼光谱将被用于监测含有非平衡数量的钚和氚同位素异构体的样品的同位素交换率。这些实验将利用Devlin最近开发的一项技术，该技术基于观察到从表面悬挂的OH基团的吸收带与参与氢键的OH基团不同。这些方法将被用于评估冰态物质的相变严重依赖于可移动的取向缺陷的假设。

Professor Devlin is supported by a grant from the Experimental Physical Chemistry Program to study icy thin films and clusters, including crystalline ice, amorphous ice and acid hydrates using infrared spectroscopy. The data acquired will enhance our understanding of natural processes such as nucleation and growth of icy particles in the atmosphere, the molecular-level processes at ice surfaces that lead to charge separation in electrical storms, and proton conductivity across and along biomembrane-water interfaces. The influence of surfaces, interfaces and intense near-infrared radiation on point-defect activities (ionic: hydrogen and hydroxyl ions, and orientational: L and D) of hydrogen-bonded solids will be examined in icy thin films and clusters, including ice I, amorphous ice, acid hydrates and clathrate hydrates. Fourier transform infrared and Raman spectroscopies will be used to monitor isotopic exchange rates for samples containing nonequilibrium quantitites of protium and deuterium isotopomers. These experiments will take advantage of a technique recently developed by Devlin based on observations that the absorption bands of OH groups that dangle from the surfaces are distinct from the OH groups which are involved in hydrogen bonds. These methods will be applied to the evaluation of the hypothesis that phase transitions of icy substances are critically dependent on the availability of mobile orientational defects.