A new strontium borophosphate,Sr6BP5O20, from synchrotron powder data

Strontium borophosphate, Sr₆BP₅O₂₀, was prepared by a solution synthesis method. The crystal structure was solved ab initio from synchrotron powder data without preliminary knowledge of the chemical formula. The compound crystallizes in space group Ic2. Sr atoms occupy sites coordinated by eight or nine O atoms, and the anionic layer consists of BO₄ and PO₄ tetra­hedra. The eightfold‐coordinated Sr atom lies at a site with twofold symmetry, while one P atom and the B atom are located on special positions of site symmetry .