title: Butane-1,2,3,4-tetra-carboxylic acid dihydrate.
abstract: The asymmetric unit of the title compound, C(8)H(10)O(8)·2H(2)O, contains one half-mol-ecule of butane-1,2,3,4-tetra-carboxylic acid and a water mol-ecule, with the complete tetra-acid generated by crystallographic inversion symmetry. Inter-molecular O-H⋯O hydrogen bonds form an extensive three-dimensional network, which consolidates the crystal packing.
authors.affiliation: State Key Laboratory Base of Novel Functional Materials and Preparation Science, Faculty of Materials Science and Chemical Engineering, Institute of Solid Materials Chemistry, Ningbo University, Zhejiang 315211, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Cheng
authors.forename: Jiang
authors.initials: J
authors.lastname: Wu
authors.forename: Hong-Lin
authors.initials: HL
authors.lastname: Zhu
authors.forename: Jian-Li
authors.initials: JL
authors.lastname: Lin