title: Octahedral tilting in MM'X4 metal-oxide organic layer structures.
abstract: Three metal-oxide organic frameworks have been synthesized and characterized: vanadium 1,4-benzenedicarboxylate, V2O2F0.6(OH)1.4(BDC).0.4H 2O (1); indium 1,4-benzenedicarboxylate, In 2F2.2(OH)1.8(BDC).1.6H2O (2); and aluminum 1,4-benzenedicarboxylate Al2F3(OH)(BDC) (3). The three-dimensional structures of 1, 2, and 3 have the same framework topology as the previously reported vanadium (III) 1,4-benzenedicarboxylate, VIII2(OH)2F2(BDC). The frameworks consist of inorganic layers constructed from corner sharing ML 6 octahedra (M=V, In, Al and L=OH, F) linked by BDC ligands. The structures are related to a general class of perovskite-related layer structures with composition MM'X4. The layers show characteristic distortions that can be related to tilting of the ML 6 octahedra. In particular the structure of 1 consists of O-V distances that strongly alternate along the b axis. The electronic consequences of this distortion then create a tilting of the 1,4-benzenedicarboxylate ligand about the a axis. Crystal data: 1, orthorhombic, space group Pmna, a=7.101(2) A, b=3.8416(11) A, c=20.570(6) A; 2, orthorhombic, space group Cmcm, a=7.490(4) A, b=21.803(1) A, c=8.154(4) A; 3, monoclinic, space group P2(1)/m, a=10.7569(8) A, b=6.7615(3) A, c=7.1291(3) A, beta=76.02(1) degrees.
authors.affiliation: Department of Chemistry, University of Houston, Houston, TX 77204-5003, USA.
authors.forename: Marie
authors.initials: M
authors.lastname: Vougo-Zanda
authors.forename: Ekaterina V
authors.initials: EV
authors.lastname: Anokhina
authors.forename: Selma
authors.initials: S
authors.lastname: Duhovic
authors.forename: Lumei
authors.initials: L
authors.lastname: Liu
authors.forename: Xiqu
authors.initials: X
authors.lastname: Wang
authors.forename: Oluwakemi A
authors.initials: OA
authors.lastname: Oloba
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Albright
authors.forename: Allan J
authors.initials: AJ
authors.lastname: Jacobson