RUI: Collaborative Research: Improvements in the Application of the Mossbauer Effect to Studies of Minerals

提出了一套穆斯堡尔谱学实验，旨在使真正定量的Fe 3+和Fe 2+的矿物含量。 将确定将峰面积与物种丰度相关联的价态和特定地点的无反冲分数“校正”系数，将在一组岩石学上重要的矿物上测试用于处理穆斯堡尔数据的四个商业软件包，并将通过一组三个软件包突出现代仪器和建模的能力，为期两年的学生项目旨在展示新技术的能力。 本项目的智力价值有四个方面：（1）改进了各种矿物的穆斯堡尔分析，（2）了解了铁在辉石中的分布，辉石是所有类地行星上常见的造岩矿物，（3）首次分析了辉晶石中铁的氧化还原状态，（4）研究了一种重要的变质矿物，在必要的、严格约束的岩石学框架内。 这项研究的更广泛的影响将是世界范围内的改进解释穆斯堡尔光谱结果从矿物学研究。 未来使用穆斯堡尔光谱法研究矿物中铁的误差将有效减少，并将证明该技术具有新的能力，可用于研究地质材料，即使是在微小的样品或铁含量低的样品中。 该项目将对六名女大学生（每年两名）产生巨大的教育影响，她们将把这些项目作为毕业论文的主题。

A set of Moessbauer spectroscopy experiments are proposed, designed to enable true quantification of Fe3+ and Fe2+ contents in minerals. Valence state- and site-specific recoil-free fraction "correction" factors for relating peak areas to species abundance will be determined, four commercially-available software packages for processing of Moessbauer data will be tested on a set of petrologically-important minerals, and the capabilities of modern instrumentation and modeling will be highlighted through a set of three, two-year student projects designed to demonstrate the abilities of the new technique. The intellectual merit of this project of this project has four aspects: (1) improvement of Moessbauer analyses of wide range of minerals, (2) understanding iron distribution in pyroxene, which is a common rock-forming mineral on all terrestrial planets, (3) enabling for the first time analyses of the redox state of iron in feldspars, and (4) study of an important metamorphic mineral, chlorite, within the necessary, well-constrained petrologic framework. The broader impact of this research will be worldwide improvements in interpreting Moessbauer spectroscopic results from mineralogical studies. The error bars on future studies of iron in minerals using Moessbauer spectroscopy will be effectively reduced, and it will be demonstrated that this technique has new capabilities that can be used to study geologic materials even in tiny samples or those with a low percentage of iron. This project will have great educational impact on the six women undergraduates (two each year) who will make these projects the topics of senior theses.