The short-range order in Li–Al–(OH−, F−) tourmalines with Y[Li/Al] ≈ 1 and different Na/Ca ratio was investigated by means of bond valence theory, experimental IR spectroscopic data and the results of X-ray single crystal diffraction. The stability of the arrangements coordinating W- and V-crystallographic sites occupied by OH−, F− and O2− ions was refined. A unified model of assignment of absorption bands in the IR spectra to the local arrangements (clusters) was suggested taking into account the first and the second OH−coordination spheres. The types of local cation arrangements around the W- and V-anion sites, alongside with clusters ratio and their distribution were brought out. The short-range order in Li–Al tourmalines controlled not only by local restrictions of the bond valence theory, but also by the long-range order was described.

中文翻译：

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Li-Al 电气石的短程有序：红外光谱、X 射线单晶衍射分析和键价理论方法

通过键价理论、实验红外光谱数据和实验结果研究了具有 Y[Li/Al] ≈ 1 和不同 Na/Ca 比的 Li-Al-(OH-, F-) 电气石的短程有序X 射线单晶衍射。协调由 OH-、F- 和 O2- 离子占据的 W-和 V-晶体学位点的排列的稳定性得到了改进。考虑到第一个和第二个 OH-配位球，建议将 IR 光谱中的吸收带分配给局部排列（簇）的统一模型。带出W-和V-阴离子位点周围的局部阳离子排列类型，以及簇比及其分布。描述了 Li-Al 电气石的短程有序不仅受键价理论的局部限制控制，而且还受长程有序的控制。