Flux growth and structure of two compounds with the EuIn2P2 structure type, AIn2P2 (A = Ca and Sr), and a new structure type, BaIn2P2

• Published in: Acta crystallographica. Section C, Crystal structure communications Vol. 65; no. 10; pp. i69 - i73
• Main Authors: Rauscher, Japheth F., Condron, Cathie L., Beault, Tanya, Kauzlarich, Susan M., Jensen, Newell, Klavins, Peter, MaQuilon, Samuel, Fisk, Zachary, Olmstead, Marilyn M.
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01-10-2009; Wiley Subscription Services, Inc
• Subjects: Chemical compounds; Chemical synthesis; Crystal structure; Crystallization; Crystallography
• ISSN: 0108-2701; 1600-5759
• DOI: 10.1107/S0108270109035987

Single crystals of the new Zintl phases AIn2P2 [A = Ca (calcium indium phosphide), Sr (strontium indium phosphide) and Ba (barium indium phosphide)] have been synthesized from a reactive indium flux. CaIn2P2 and SrIn2P2 are isostructural with EuIn2P2 and crystallize in the space group P63/mmc. The alkaline earth cations A are located at a site with m symmetry; In and P are located at sites with 3m symmetry. The structure type consists of layers of A2+ cations separated by [In2P2]2− anions that contain [In2P6] eclipsed ethane‐like units that are further connected by shared P atoms. This yields a double layer of six‐membered rings in which the In—In bonds are parallel to the c axis and to one another. BaIn2P2 crystallizes in a new structure type in the space group P21/m with Z = 4, with all atoms residing on sites of mirror symmetry. The structure contains layers of Ba2+ cations separated by [In2P2]2− layers of staggered [In2P6] units that form a mixture of four‐, five‐ and six‐membered rings. As a consequence of this more complicated layered structure, both the steric and electronic requirements of the large Ba2+ cation are met.