High-temperature, high-pressure hydrothermal synthesis and characterization of a new framework stannosilicate: Cs2SnSi3O9

A new stannosilicate Cs2SnSi3O9 has been synthesized and characterized by single-crystal X-ray diffraction and solid-state NMR spectroscopy. It crystallizes in the orthorhombic space group P212121 (No. 19) with image, image, image, image, and image with image. The structure consists of helical silicate chains with a period of six tetrahedra which are connected by SnO6 octahedra to form a 3D framework containing 6-ring and 7-ring channels where the Cs+ cations reside. This work is one of the few studies concerning the synthesis of stannosilicates under high-temperature and high-pressure hydrothermal conditions.