Abstract
The crystal structure of Cs0.35Al0.35Si2.65O6 has been determined with direct methods from X-ray four-circle single-crystal diffractometer data at 293 K. The space group is monoclinic, B21 with Z = 4; a = 7.3585(4) Å; b = 5.0334(3) Å; c = 15.950(1) Å; β = 90.778(9)0; V = 590.7 Å3; D c = 2.55g cm−3, D m = 2.56g cm−3. The refinement converged to R = 0.044. The aluminosilicate framework is isotypical with the framework of bikitaite. The Cs atom is located in the large channel coordinated by ten oxygens in the range 3.24 Å to 3.58 Å.