title: Crystal engineering of urea alpha-network via I...O2N synthon and design of SHG active crystal N-4-iodophenyl-N'-4'-nitrophenylurea.
abstract: Crystalline nitrodiphenyl ureas adopt the N-H...O tape alpha-network only when stabilization accrues from the I...O(2)N or C[triple bond]C-H...O(2)N synthon, otherwise the ureanitro motif is preferred; soft, weak interactions can direct polar self-assembly in strong N-HO hydrogen-bonded crystals.
authors.affiliation: School of Chemistry, University of Hyderabad, Hyderabad, 500 046, India.
authors.forename: Sumod
authors.initials: S
authors.lastname: George
authors.forename: Ashwini
authors.initials: A
authors.lastname: Nangia
authors.forename: Chi-Keung
authors.initials: CK
authors.lastname: Lam
authors.forename: Thomas C W
authors.initials: TC
authors.lastname: Mak
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Nicoud
mesh_terms: D002616:Chemical Engineering / Q000379:methods*; D003460:Crystallization; D014508:Urea / Q000032:analysis / Q000138:chemical synthesis*
chemical_list: D014508:Urea