Proton and Ligand Interactions at Single Crystal Mineral/ Water Interfaces Using Scanning Probe Microscopy and Optical Second Harmonic Generation

环境地球化学和生物化学计划的这个奖项是 由地球科学和化学司以及 刺激竞争研究实验计划（EPSCoR）。 博士 卡里克·M埃格莱斯顿和史蒂芬·R.地质学的希金斯和 怀俄明州大学地球物理系将开发方法， 在矿物表面测量中实现晶面特异性 消费标准. 这项研究的目标是超越表面平均水平， 有助于了解矿物表面的信息途径 反应性 表面电荷和电位作为pH值的函数， 将使用原子力显微镜（AFM）测量离子介质， 原位光学二次谐波产生（SHG）光谱法 代表性矿物表面，例如刚玉、赤铁矿、金红石和 石英。 这些测量结果将与 有机分子在矿物-水界面上的吸附。 的 感兴趣是柠檬酸、草酸、对硝基苯甲酸和 4，5-二硝基苯-1，2-二羧酸和罗丹明。 了解有机和生物化合物与矿物的反应 表面对于完成表征越来越重要， 复杂的地质和环境过程。 目前矿物表面地球化学中使用的方法 足够了。 在这里，AFM和SHG仪器的能力将是 作为表征矿物表面的手段进行测试， 在“真实的世界”样本中。

This award in the Environmental Geochemistry and Biochemistry Program is supported by the Divisions of Earth Sciences and Chemistry and the Experimental Program to Stimulate Competitive Research (EPSCoR). Dr. Carrick M. Eggleston and Dr. Steven R. Higgins of the Geology and Geophysics Department, University of Wyoming, will develop methods to achieve crystal-face specificity in the measurement of mineral surface charge. The goal of the research is to move beyond a surface-average approach to information helpful to understanding mineral surface reactivity. The surface charge and potential as a function of pH and ionic media will be measured using atomic force microscopy (AFM) and in-situ optical second harmonic generation (SHG) spectroscopy for representative mineral surfaces, such as, corundum, hematite, rutile and quartz. These measurements will be compared to results obtained after the adsoprtion of organic molecules at the mineral-water interface. Of interest are citric, oxalic, p-nitrobenzoic, and 4,5-dinitrobenzene-1,2-dicarboxylic acids and rhodamine. Understanding reactions of organic and biological compounds with mineral surfaces are increasingly important to complete characterization of complex geological and environmental processes at the molecular level. The methods currently used in mineral surface geochemistry are not adequate. Here, the capabilities of AFM and SHG instrumentation will be tested as means of characterizing the surfaces of mineral surfaces found in `real world` samples.