title: 4,4'-Dimeth-oxybi-phenyl-3,3'-di-car-box-ylic acid.
abstract: The title compound, C16H14O6, was recrystallized under solvothermal conditions. The mol-ecules are located on inversion centres, with one complete mol-ecule generated from the asymmetric unit by inversion. There are intra-molecular O-H⋯O hydrogen bonds involving the carb-oxy-lic acid group and the O atom of the adjacent meth-oxy group. In the crystal, mol-ecules are linked via O-H⋯O hydrogen bonds, forming chains propagating along [100]. The chains are linked via C-H⋯O hydrogen bonds, forming sheets parallel to (001).
authors.affiliation: Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Lundvall
authors.affiliation: Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway ; inGAP National Centre of Research-based Innovation, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway.
authors.forename: David Stephen
authors.initials: DS
authors.lastname: Wragg
authors.affiliation: Department of Chemistry, University of Bergen, PO Box 7803, 5020 Bergen, Norway.
authors.forename: Pascal D C
authors.initials: PD
authors.lastname: Dietzel
authors.affiliation: Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1126, 0315 Oslo, Norway.
authors.forename: Helmer
authors.initials: H
authors.lastname: Fjellvåg