W0136

Hydrothermal Synthesis and Structural Studies of Open Frameworks Indium Phosphates and Arsenates. Xuejiao Tang and Lachgar Abdessadek, Department of Chemistry, Wake Forest University, Winston-Salem, NC, 27109 USA

Aluminophosphates and gallophosphates are well known for their structural diversity and catalytic properties. Recently, there has been an increasing interest in the chemistry of indium phosphates/arsenates in an effort to better understand the composition-structure-properties relationships of Group 13 phosphates/arsenates. Our work in this area focuses on the synthesis and characterization of compounds with open frameworks. Using hydrothermal synthesis techniques at temperatures between 150 and 200[hammer] C, we have prepared four new compounds: RbIn(HPO₄)₂ (1), RbIn(HAsO₄)₂ (2), Ba₃In₂(HPO₄)₆ (3), and Ba₃In₂(HAsO₄)₆ (4). All compounds have three-dimensional frameworks built up by corner-sharing InO₆ octahedra and HPO₄/HAsO₄ tetrahedra. The frameworks generate tunnels with different sizes. The two rubidium compounds are not isostructural. The tunnels in the framework of compound (1) have 12-membered ring opening and are parallel to [100] direction, whereas the tunnels in compound (2) have 8-membered ring opening. These tunnels are running along [100], [010], and [001] directions and intersect each other. Compound (3) and (4) are isostructural. Their frameworks generate tunnels similar to those in compound (2). Crystal data: compound (1): a = 5.2924(3) Å, b = 8.9107(5) &Arin = 95.132(5)[hammer] , P2₁/c, Z = 4; compound (2): a = 8.534(1)Å, c = 56.57(1)Å, Rc, Z = 12; compound (3): a = 9.6243(4)Å, c = 37.180(2)Å, Rc, Z = 6; compound (4): a = 9.9882(4)Å, c = 37.565(3)Å, Rc, Z = 6.