In the title compound, the cyclo­octene ring has a boat–chair conformation.

The title compound consists of two N-methyl-2-iodo­indole units linked by a thio­ether bridge in a gauche conformation. In the crystal, short I⋯C and I⋯π contacts dominate the packing and generate a herringbone motif.

In the title compound, the pendant para toluene moieties are inclined to the central naphthalene-2,3-dicarbo­nitrile grouping by 45.82 (7) and 42.41 (6)°. The crystal packing features offset parallel π–π stacking and C—H⋯π inter­actions.

The syntheses and crystal structures of three complexes with the composition ZnCl2(2,6-di­methyl­pyrazine)(CH3OH) (1), ZnBr2(2,6-di­methyl­pyrazine)(CH3OH) (2) and ZnI2(2,6-di­methyl­pyrazine)(H2O) (3) are reported. Each consists of discrete complexes that are linked by hydrogen bonding.

The synthesis and crystal structure of a new organic compound, 2,6-bis­[4-(eth­oxy­carbon­yl)-5-methyl­pyrazol-1-yl]pyridine is reported. A detailed analysis of the inter­molecular contacts in the crystal packing was performed using Hirshfeld surface analysis.

The crystal structure of Na4(As2O5)(H2O)0.5 consists of a half-eclipsed (As2O5)4– anion embedded in a framework of [NaO4] and [NaO6] polyhedra. O—H⋯O hydrogen-bonding consolidates the packing.

The title compound crystallizes in the monoclinic space group P21. The luteolin mol­ecule adopts a planar conformation, and the crystal structure is consolidated by extensive hydrogen-bonding inter­actions.

The title cocrystal was obtained by the cocrystallization of 1-phenyl­semicarbazide (A) and 1-phenyl­pyrazolidin-3-one (B) in a 1:1 molar ratio from methanol solution. The structure features a gauche arrangement about the N—N bond in the semicarbazide fragment and a twisted conformation of the pyrazolidinone ring. In the extended structure, the mol­ecules are linked by A → A and B → A N—H⋯O hydrogen bonds, supplemented by C—H⋯π contacts to generate a three-dimensional supra­molecular framework.

The title compound, [SmI2(C22H28O7)]·0.5C4H10O2 or Sm(dibenzo-21-crown-7)I2, was obtained as a minor product by layering di­meth­oxy­ethane solutions of SmI2 and dibenzo-21-crown-7. The asymmetric unit consists of one Sm(dibenzo-21-crown-7)I2 moiety and half a di­meth­oxy­ethane solvent mol­ecule in the outer sphere.

The title compound (Z)-3-{2-[(Z)-11H-indeno­[1,2-b]quinoxalin-11-yl­idene]hydrazin­yl}-N-phenyl­but-2-enamide monohydrate was synthesized and investigated using SCXRD. Except for the phenyl group, the mol­ecule is almost planar, and includes an intra­molecular Nhydrazin­yl—H⋯(Ocarbon­yl, Nquinoxaline) hydrogen-bond system. Hydrogen bonds combine to form a layer structure.

The asymmetric unit of the title compound contains two crystallographically independent ferrocenecarboxaldehyde mol­ecules. In the crystal, C—H⋯O hydrogen bonds link the mol­ecules into infinite chains along the b-axis direction. The hydrogen bonding, π–π, C—H⋯π(ring) and van der Waals inter­actions are the dominant inter­actions in the crystal packing.

The tetra­cyclic ring systems of the two title structures are essentially planar. Mol­ecules are linked by hydrogen bonds N—H⋯O&z-dbnd;P, forming rings of graph set R22(12).

A π-conjugated N-donor ligand links μ2-iodido-bridged dinuclear [Bi2I8]2− units to afford a rare one-dimensional anionic iodido­bis­muth(III) coordination polymer, which was synthesized and structurally characterized by single-crystal X-ray diffraction.

The crystal structures of ZnCl2(C4H5N3)2 (second polymorph) and ZnI2(C4H5N3)2 were determined. Both are built up from discrete tetra­hedral complexes that are connected via inter­molecular hydrogen bonds.

The structure of a a hexa­kis­(imidazole)­cobalt(II) bis­(benzene-1,3,5-tri­carboxyl­ate) tetra­(imidazole-1-ium) dihydrate compound was determined by single-crystal X-ray diffraction.

In the complex anion of the title salt, the central MnII atom adopts a distorted octa­hedral coordination environment, defined by two aqua, two chlorido, and one bidentate malonato ligand. The thia­diazole ligands are protonated and linked to the anion through various hydrogen-bonding inter­actions.

The crystal structure of [Ca2(C6H5NO2)2(H2O)2(NO3)2] reveals an eight-coordinate distorted dodeca­hedral CaII center with mixed ligands. A Hirshfeld surface analysis elucidated the inter­molecular inter­actions consolidating the crystal.

The single-crystal X-ray diffraction structures of an azo­benzene-bridged aza-18-crown-6 cryptand and its sodium complex are reported.

Two 2-oxo-2H-chromene derivatives were synthesized by acid–aniline coupling reactions. These two compounds were subjected to SXRD and Hirshfeld surface analysis to explore their inter­molecular inter­actions.

A second ortho­rhom­bic polymorph of the title Schiff base crystallizes in space group Pna21, compared to Pbca for the first polymorph. The difference in the structure of the two polymorphs resides in the orientation of the 4-meth­oxy moiety of the (4-meth­oxy­phen­yl)allyl­idene unit.

The syntheses and structures of [ZnI2(C6H8N2)]n and [ZnI2(C6H8N2)(H2O)]·0.5C6H8N2·0.5H2O are reported (C6H8N2 = 2,3-di­methyl­pyrazine). In the first compound, the Zn2+ cations are connected by the 2,3-di­methyl­pyrazine ligands into helical chains, whereas in the second discrete complexes are observed that are arranged in such a way that cavities are formed, in which additional water and 2,3-di­methyl­pyrazine mol­ecules are incorporated.

The monoclinic and ortho­rhom­bic polymorphs of 2,6-di­methyl­phenol are constituted of very similar hy­dro­gen-bonded chains, but the packing of the chains differs significantly.

The asymmetric unit of the title com­pound contains two mol­ecules. In the crystal, C—H⋯O and C—H⋯Cl hy­dro­gen bonds link the mol­ecules into two-dimensional networks, enclosing R33(19), R22(18) and R22(14) ring motifs. C—H⋯π inter­actions help to consolidate the packing.

Single crystals of 2-amino-4-nitro­imidazole hydro­chloride were synthesized by slow evaporation and characterized by X-ray diffraction. The crystal structure features a planar imidazolium cation and a chloride anion, forming a three-dimensional supra­molecular network via N—H⋯Cl and N—H⋯O hydrogen bonds.

The reaction of ZnCl2 with PCl5 in a 1:1 molar ratio at 623 K produced single crystals of ZnPCl7, which crystallizes in the ortho­rhom­bic space group Ama2. Its extended structure features isolated [PCl4]+ tetra­hedra and one-dimensional chains of corner-sharing ZnCl2Cl2/2 tetra­hedra.

In the title compound, the carbon tetra­chloride solvent mol­ecule is presumed to have originated as an impurity in the chloro­form solvent used. In the extended structure, the cation and anion are linked by an N—H⋯O hydrogen bond. Along with electrostatic forces, C—H⋯N, C—H⋯S and C—H⋯O hydrogen bonds help to consolidate the crystal packing.

The crystal structures and Hirshfeld surface analyses of two similar azo compounds are reported. In the first, the mol­ecules form layers parallel to the (010) plane through C—H⋯π and C—Cl⋯π inter­actions and van der Waals inter­actions between these layers consolidate the packing. In the other, the mol­ecules are connected by C—H⋯O and C—H⋯Cl hydrogen bonds, forming a three-dimensional network. C—Cl⋯π inter­actions also contribute to the packing.

In the title compound, the crystal packing features C—H⋯Cl hydrogen bonds, which form R22(12) graph-set motifs.

The crystal structure of tris­[4-(3,4-di­meth­oxy­thio­phen-2-yl)phen­yl]amine (DMOT-TPA) was determined by X-ray diffraction. The central nitro­gen atom is non-pyramidal, with the three para-phenyl­ene rings in a propeller arrangement. The thio­phene rings are twisted by ca. 25–29° relative to the phenyl­ene rings, forming a distorted π-conjugated framework. In the crystal, C—H⋯π inter­actions link mol­ecules into two-dimensional sheets and a three-dimensional network.

The crystal structure of the title compound N-hy­droxy-4-{2-[(2-hy­droxy­eth­yl)(phen­yl)amino]-2-oxoeth­yl}benzamide monohydrate (HPOB·H2O) is reported.

In the title compound, the central zinc(II) ion coordinated by four 5-phenyl­imidazole ligands, with two nitrate anions providing charge balance·In the crystal, the nitrate ions occupy the voids formed by the [Zn(C9H8N2)4]2+ cations and function as counter-ions. The nitrate oxygen atoms participate in weak N—H⋯O hydrogen-bonding inter­actions.

The isotypic strontium analogue of the mineral henmilite, Sr2Cu(OH)4[B(OH)4]2, displays a quasi two-dimensional spin system with CuII ions.

The crystal structure of a new complex between the theophylline ligand and palladium has been elucidated.

The crystal structures of a solvated and an unsolvated di­thio­carbazate imine derivatives are compared and contrasted.

The title asymmetric biazolpyridine crystallizes in the triclinic space group P1 with two independent mol­ecules in the asymmetric unit. Structural and Hirshfeld surface analysis revealed key non-covalent inter­actions such as C—H⋯N/C/O and π–π stacking, which consolidate the crystal structure.

In the crystal, C—H⋯O hydrogen bonds link the mol­ecular pairs to form dimers with an R22(16) ring motif. Additionally, ribbons are formed along the [101] direction by C—H⋯π inter­actions. van der Waals inter­actions between the ribbons contribute to the cohesion of the mol­ecular packing.

In the title RuII complex, a meridionally bound 4,4′,4′′-tris­(meth­oxy­carbon­yl)terpyridine and a di­meth­oxy­phenyl­phosphine ligand define a distorted trans-RuN3PCl2 octa­hedral coordination environment, and water mol­ecules of crystallization bridge pairs of complex mol­ecules into discrete hydrogen-bonded dimers.

The title compound [Fe(C21H13N3S)(CO)(PMe3)2] exhibits a square-pyramidal geometry, distinct from the trigonal–bipyramidal geometry in [Fe(C21H13N3S)(CO)3], due to the σ-donating properties of the two tri­methyl­phosphane ligands. An increase in π-back-donation from the electron-rich iron center to the pyridazine moiety was also confirmed.

The title compounds exhibit a consistent pattern of inter­molecular O—H⋯O hydrogen bonds, forming a C(7) zigzag chain propagating in the [010] direction in each case.

The crystal structure of racemic calcium 5-methyl­tetra­hydro­folate trihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques.

The title compounds have different local symmetries but a consistent supra­molecular motif of zigzag supra­molecular ribbons propagating along the [100] direction linked by N—H⋯N and N—H⋯O hydrogen bonds. Various weak inter­actions consolidate both structures.

The title compound crystallizes with two independent mol­ecules in the asymmetric unit, which are connected into chains by N—H⋯O hydrogen bonds.

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The extended structure of the title salt features a network of N—H⋯O, O—H⋯O, and C—H⋯O hydrogen bonds, which generate infinite layers.

A paper-based virtual X-ray diffraction experiment, which is based on the right-angle condition for constructive inter­ference, allows the implications of Bragg's law to be studies in a simple way.

The structure of a tris­[hexa­kis­(imidazole)­cobalt(II)] bis­(benzene-1,3,5-tri­carboxyl­ate) compound was determined by single-crystal X-ray diffraction.

The (modified) triazine ring in the title compound is planar. The packing involves classical and ‘weak' hydrogen bonds, together with π contacts to the triazine ring.

In the complex [Ag(2AB)2]NO3·(2AB)2 (2AB: 2-amino­benzoxazole), the central silver atom is coordinated monodentately by two 2AB ligands forming a linear geometry. The extended structure features N—H⋯N, N—H⋯π and π–π inter­actions.

Single-crystal X-ray diffraction studies were performed on two new forms of tinidazole: triclinic and hemihydrate, and their structures were compared to that of the known monoclinic form.

Treatment of a tetra­(aceto­nitrile)­copper(I) precursor with excess xylyl isocyanide forms the title tetra­(isocyanide)copper(I) complex, which was characterized structurally and spectroscopically.