Feldspars are major components of terrestrial planetary surfaces. For future space application and the setup of a comprehensive reference database, Na- and K-rich alkali feldspars, NaAlS i 3 O 8 – KAlS i 3 O 8 , have been investigated by infrared reflectance spectroscopy. We related the feldspar spectra to the chemical composition and state of Al,Si order/disorder. The infrared measurements were analyzed with respect to band shifts and peak shapes using the autocorrelation function. Natural samples served as starting materials. Some samples were treated by the alkali exchange method to produce pure end-members, which were then heated to generate various states of Al,Si disorder. X-ray diffraction (XRD) methods served to determine the Al,Si distribution. Our autocorrelation allowed to differentiate between the compositional and the order/disorder influences seen in the spectra in the wavelength range between 7 μ m up to 14 μ m (1429 cm − 1 to 714 cm − 1 ). Space missions often analyze the surfaces of planetary bodies using remote sensing. Therefore, our results are essential to characterize and distinguish alkali feldspars on the surfaces of terrestrial planetary bodies like Mercury.

中文翻译：

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空间应用碱性长石样品的中红外光谱

长石是地球行星表面的主要成分。为了未来的空间应用和综合参考数据库的建立，已经通过红外反射光谱研究了富含钠和钾的碱长石 NaAlS i 3 O 8 – KAlS i 3 O 8 。我们将长石光谱与 Al、Si 有序/无序的化学成分和状态相关联。使用自相关函数分析了红外测量的带移和峰形。天然样品作为起始材料。一些样品通过碱交换法处理以产生纯端元，然后将其加热以产生各种状态的Al、Si无序。X射线衍射(XRD)方法用于确定Al、Si分布。我们的自相关允许区分在 7 μm 到 14 μm（1429 cm - 1 到 714 cm - 1 ）之间的波长范围内的光谱中看到的成分和有序/无序影响。太空任务经常使用遥感分析行星体的表面。因此，我们的结果对于表征和区分水星等类地行星体表面的碱性长石至关重要。