Crystal truncation rod (CTR) X-ray diffraction is an invaluable tool for measuring mineral surface and adsorbate structures, and has been applied to several environmentally and geochemically important systems. Traditionally, the method has been restricted to single crystals with lateral dimensions >3 mm. Minerals that meet this size criterion represent a minute fraction of those that are relevant to interfacial geochemistry questions, however. Crystal screening, data collection, and CTR measurement methods have been developed for crystals of <0.3 mm in lateral size using the manganese oxide mineral chalcophanite (ZnMn₃O₇·3H₂O) as a case study. This work demonstrates the feasibility of applying the CTR technique to previously inaccessible surfaces, opening up a large suite of candidate substrates for future study.

晶体截断棒 (CTR) X 射线衍射是测量矿物表面和吸附结构的宝贵工具，已应用于多个环境和地球化学重要系统。传统上，该方法仅限于横向尺寸 >3 mm 的单晶。然而，满足这一尺寸标准的矿物只占与界面地球化学问题相关的矿物的一小部分。使用氧化锰矿物黄铜矿 (ZnMn ₃ O ₇ ·3H ₂O) 作为案例研究。这项工作证明了将 CTR 技术应用于以前难以接近的表面的可行性，为未来的研究开辟了大量候选基材。