Upgrading of the Vibrational Spectroscopy Laboratory at Virginia Tech

在过去的十年中，测量固体、液体和气体振动光谱的仪器取得了重大进展。 现代拉曼微探针使用特定波长的聚合物陷波滤波器来去除入射辐射和杂散光。 早期的设计是通过使用一系列反射镜和透镜将拉曼信号聚焦到检测器上来实现这一点的，沿着光束路径有相当大的能量损失。因此，现代的拉曼仪器具有更高的能量通量，同时，对所有共价键合的物质的检测极限显著降低。该项目将通过获得一个采用可见波长激光（514 nm）的拉曼微探针以及一个采用紫外激光（325 nm）作为激发源的最先进系统来提升弗吉尼亚理工大学振动光谱实验室的能力。 与可见光系统不同，后者不受样品荧光的影响，允许分析有机化合物和其他在照明时发荧光的相。 这些仪器将应用于各种新的和进行中的项目，包括开发确定硅酸盐熔体包裹体含水量的技术、含二氧化碳和甲烷流体包裹体的定量分析、石油流体包裹体的分析以及自然和人为环境中腐蚀产物的现场定性。

EAR-0322119BodnarDuring the past decade significant advances have been made in instrumentation for measuring the vibrational spectra of solids, liquids and gases. Modern Raman microprobes use a wavelength-specific polymer notch filter to remove incident radiation and stray light. Earlier designs accomplished this through use of a series of mirrors and lenses that focused the Raman signal onto the detector, with considerable loss of energy along the beam path. As a result, modern Raman instruments have much higher energy throughput and concomitantly, significantly lower detection limits for all covalently bonded species. This project will upgrade the capabilities of the Vibrational Spectroscopy Laboratory at Virginia Tech by acquiring a Raman microprobe that employs a visible wavelength laser (514 nm), as well as a state of the art system that uses an ultraviolet laser (325 nm) as the excitation source. Unlike the visible system, this latter system is not affected by fluorescence from the sample, permitting analysis of organic compounds and other phases that fluoresce when illuminated. The instruments will be applied in a variety of new and ongoing projects, including development of techniques for determining water contents of silicate melt inclusions, quantitative analysis of carbon dioxide and methane-bearing fluid inclusions, analysis of petroleum fluid inclusions and in situ characterization of corrosion products in natural and anthropogenic environments.