The crystallographic analysis of the structures of danburite CaSi2B2O8, which is orthorhombic (Pnma) at normal pressure, triclinic (P1¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{1}$$\end{document}) at a pressure of 25.4 GPa, and monoclinic (P21/c) at a pressure of 32.3 GPa, shows that they are based on a joint packing of Ca cations and O anions whose regularity increases with pressure. A common structural fragment is the configuration of atoms related by the glide reflection plane retaining for Ca and a part of O, B positions with a possible Si migration according to the seesaw mechanism (N. V. Belov).

中文翻译：

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丹布里石 CaSi2B2O8 相变的晶体学分析

danburite CaSi2B2O8 结构的晶体学分析，其在常压下为正交（Pnma），三斜（P1¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{ amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\bar{1}$$\end{document}) 在压力下25.4 GPa，单斜晶 (P21/c) 压力为 32.3 GPa，表明它们是基于 Ca 阳离子和 O 阴离子的联合堆积，其规律性随压力增加。根据跷跷板机制（NV Belov），一个常见的结构片段是由滑行反射面保留的 Ca 和部分 O、B 位置与可能的 Si 迁移相关的原子配置。