The crystal structure of the title compound, [Cu2(C18H12Br2N4O2S2)2], consists of binuclear complex units which lie across inversion centres and are connected by weak Cu-O coordination bonds forming chains along the b axis. The CuII ion is five-coordinated by two N atoms and two O atoms of the chelating ligand and one symmetry-related O atom forming a square-pyramidal coordination geometry. In ...

In this paper, Kekule structures of benzenoid chains are considered. It has been shown that the coefficients of a B_n (x) Morgan-Voyce polynomial equal to the number of k-matchings (m(G,k)) of a path graph which has N=2n+1 points. Furtermore, two relations are obtained between regularly zig-zag nonbranched catacondensed benzenid chains and Morgan-Voyce polynomials and between regularly zig-zag ...

In the title compound, C(4)H(10)NO(+)·C(4)H(5)O(6) (-)·H(2)O, the morpholine ring adopts a chair conformation. In the crystal, the tartrate anions are linked via O-H⋯O hydrogen bonds, forming chains propagating along [101]. These chains are linked via N-H⋯O and O-H⋯O hydrogen bonds, involving the morpholinium cation and the water molecule, forming a three-dimensional network.

In the crystal structure of the title compound, C5H14N2 (2+)·2HC2O4 (-), the two crystallographically independent hydrogen oxalate anions are linked by strong inter-molecular O-H⋯O hydrogen bonds, forming two independent corrugated chains parallel to the b axis. These chains are further connected by N-H⋯O and C-H⋯O hydrogen bonds originating from the organic cations, forming a three-dimensional...

The title compound, C23H22FN5S, exists in a trans conformation with respect to the methene C=C and the acyclic N=C bonds. The 1,2,4-triazole-5(4H)-thione ring makes dihedral angles of 88.66 (9) and 84.51 (10)°, respectively, with the indole and benzene rings. In the crystal, mol-ecules are linked by pairs of N-H⋯S hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. The dimer...

In the title salt, C(6)H(10)N(3)O(2) (+)·C(7)H(7)O(3)S(-), the 2-amino-4,6-dimeth-oxy-pyrimidinium cation inter-acts with the sulfonate group of the p-toluene-sulfonate anion via a pair of N-H⋯O hydrogen bonds, forming a cyclic hydrogen-bonded R(2) (2)(8) motif, which in the crystal is linked by further intemolecular N-H⋯O hydrogen bonds, forming supra-molecular chains along the c axis. Further...

The racemic title compound, C(3)H(5)Br(2)NO, was crystallized from methanol. In the crystal, adjacent mol-ecules are linked through N-H⋯O hydrogen bonds, forming chains along the c-axis direction. These chains are linked through N-H⋯O hydrogen bonds, forming an undulating two-dimensional network lying parallel to the bc plane. There are also short Br⋯Br contacts present [3.514 (3) Å].

In the title mol-ecular salt, C6H9N2 (+)·C7H4NO4 (-), the original pyridine N atom of 2-amino-4-methyl-pyridine is protonated and the carb-oxylic acid group of nitro-benzoic acid is deprotonated. In the crystal, the ions are linked by N-H⋯O hydrogen bonds, forming chains propagating along [001]. The chains are linked via C-H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to t...

In the title mol-ecule, C18H19BrN2O, the benzene ring is inclined to the oxa-diazole ring by 10.44 (8)°. In the crystal, C-H⋯π inter-actions link the mol-ecules in a head-to-tail fashion, forming chains extending along the c-axis direction. The chains are further connected by π-π stacking inter-actions, with centroid-centroid distances of 3.6385 (7) Å, forming layers parallel to the bc plane.

In the crystal structure of the title compound, C(6)H(7)N(2)O(2) (+)·NO(3) (-), the cations are linked via C-H⋯O hydrogen bonds, forming infinite chains running along the b axis. These chains are further linked through N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds to the nitrate anions, forming well-separated infinite planar layers parallel to (001).