Synthesis and Crystal Structure of the Strontium Beryllate Sr 3 Be 2 O 5

Beryllates show an interesting and diverse structural chemistry, resembling that of well‐investigated silicates. The coexistence of tetrahedral and trigonal coordination of Be by O atoms in oxoberyllates allows for an even broader variety of structural motives and implies a plurality of possible atomic ratios Be:O in ternary or higher compounds. We have now synthesized the novel strontium oxoberyllate Sr 3 Be 2 O 5 via a high‐temperature high‐pressure reaction and have structurally characterized the ternary oxide by single‐crystal and powder X‐ray diffraction analysis. Sr 3 Be 2 O 5 , a low condensed oxoberyllate, contains unprecedented [Be 2 O 5 ] 6– double triangles and Sr atoms in both double‐capped trigonal‐prismatic and octahedral coordination. These motifs show striking resemblance to α‐SrBeO 2 and SrO, combining their structural properties. Lattice energy (MAPLE) calculations corroborate found parallels to the known phases SrO and α‐SrBeO 2 .