RUI: Crystal Growth Speedometry, Micro-Fourier Transform InfraRed (FTIR) Spectroscopy of Minerals

威斯康星大学欧克莱分校的这项建议的主要目的是利用在结晶过程中并入水热晶体中的H-物种缺陷来确定不同晶面的相对生长速度，进而可以通过适当的实验校准来推导出原位晶体生长的绝对时间。将对石英和蓝晶石进行调查。晶体生长过程中涉及的时间尺度很少受到限制，从火成岩或变质环境中生长晶体所涉及的绝对时间尚不清楚。这是岩石学中的一个一阶问题，很少有人提出新的方法来解决它。尽管描述地壳环境中反应动力学的理论是合理的，但很少有定量研究，导致单个晶面大小和形状变化的机制仍然不太清楚。我们实验室获得的天然真面体石英晶体的公开数据使我们能够定量地确定它们在整个生长历史中生长面的相对生长速度。在生长时，水分子和金属羟基杂质在晶体结构中的浓度是直接反映活跃生长面生长动力学的“里程表”。这些测量提供了一种新的方法来成像晶体在整个生长历史中的形状和绝对尺寸。与商业石英生产公司的合作将为流体参数的实验校准提供合成样品，这些参数对于定量解释来自天然热液石英晶体的氢缺陷数据是必要的。

AbstractEAR-0126285IhingerUniversity of Wisconsin-Eau ClaireThe primary objective of this proposal is to use H-species defects, incorporated into hydrothermal crystals during crystallization, to determine the relative growth rates of different crystallographic faces, which in turn may be used to derive the absolute time for in situ crystal growth, with appropriate experimental calibration. Quartz and kyanite will be investigated. The timescales involved in crystal growth processes are poorly constrained and the absolute time involved in the growth of crystals from either igneous or metamorphic environments is not known. This is a first order problem in petrology and few new approaches have been proposed to attack it. Although the theory describing reaction kinetics in the crustal environment is sound, few quantitative studies exist and the mechanisms responsible for the variation in size and shape of individual crystal faces are still not well understood. Published data on natural euhedral quartz crystals obatined in our laboratory allow quantitative determination of the relative growth rates of their growth faces throughout their growth histories. The concentration of water molecules and metal hydroxyl impurities incorporated into the crystal structure at the time of growth serve as "speedometers" that directly reflect the growth kinetics of active growth faces. These measurements provide a new means of imaging the shape and absolute dimensions of crystals throughout their growth history. A partnership with commercial quartz production company will provide synthetic samples for experimental calibration of fluid parameters, which are necessary to quantitatively interpret H-defect data from natural hydrothermal quartz crystals.