title: Urea-adipic acid (2/1).
abstract: The asymmetric unit of the title co-crystal, 2CH(4)N(2)O·C(6)H(10)O(4), contains two urea mol-ecules and two half-mol-ecules of adipic acid; the latter are completed by crystallographic inversion symmetry. The crystal packing is stabilized by O-H⋯O and N-H⋯O hydrogen bonds, generating a chain along [110]. Additional weak inter-chain O-H⋯O and N-H⋯O inter-molecular inter-actions lead to the formation of a three-dimensional network.
authors.affiliation: Center of Applied Solid State Chemistry Research, Ningbo University, Ningbo, Zhejiang 315211, People's Republic of China.
authors.forename: Hai-Sheng
authors.initials: HS
authors.lastname: Chang
authors.forename: Jian-Li
authors.initials: JL
authors.lastname: Lin