dl-Asparaginium perchlorate

Two enantiomeric counterparts (l- and d-asparginium cations related by glide planes) are present in the structure of the title compound, C4H9N2O3 +·ClO4 −, with a 1:1 cation–anion ratio. The structure is built up from asparginium cations and perchlorate anions. In the crystal, mol­ecules assemble in double layers parallel to (100) through N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds. In the asparginium layers, hydrogen bonds generate alternating R 2 2(8) and R 4 3(18) graph-set motifs. Further hydrogen bonds involving the anions and cations result in the formation of a three-dimensional network

Adeninium cytosinium sulfate

In the title compound, C5H6N5 +·C4H6N3O+·SO4 2−, the adeninium (AdH+) and cytosinium (CytH+) cations and sulfate dianion are involved in a three-dimensional hydrogen-bonding network with four different modes, viz. AdH+⋯AdH+, AdH+⋯CytH+, AdH+⋯SO4 2− and CytH+⋯SO4 2−. The adeninium cations form N—H⋯N dimers through the Hoogsteen faces, generating a characteristic R 2 2(10) motif. This AdH+⋯AdH+ hydrogen bond in combination with AdH+⋯CytH+ H-bonds leads to two-dimensional cationic ribbons parallel to the a axis. The sulfate anions inter­link the ribbons into a three-dimensional hydrogen-bonding network and thus reinforce the crystal structure

Adeninium 3-carboxy­anilinium bis­(perchlorate) trihydrate

In the title salt, C5H6N5 +·C7H8NO2 +·2ClO4 −·3H2O, the 3-carboxy­anilinium and adeninium cations are monoprotonated at the amino group and at a pyrimidine N atom respectively. In the crystal, the components are involved in extensive three-dimensional hydrogen-bonding networks composed of O—H⋯O, N—H⋯O, O—H⋯N, N—H⋯N and C—H⋯O inter­actions. Bifurcated hydrogen bonds are observed between perchlorate O atoms and adeninium cations

dl-Asparaginium nitrate

In the title compound, C4H9N2O3 +·NO3 −, alternatively called (1RS)-2-carbamoyl-1-carboxy­ethanaminium nitrate, the asymmetric unit comprises one asparaginium cation and one nitrate anion. The strongest cation–cation O—H⋯O hydrogen bond in the structure, together with other strong cation–cation N—H⋯O hydrogen bonds, generates a succession of infinite chains of R 2 2(8) rings along the b axis. Additional cation–cation C—H⋯O hydrogen bonds link these chains into two-dimensional layers formed by alternating R 4 4(24) and R 4 2(12) rings. Connections between these layers are provided by the strong cation–anion N—H⋯O hydrogen bonds, as well as by one weak C—H⋯O inter­action, thus forming a three-dimensional network. Some of the cation–anion N—H⋯O hydrogen bonds are bifurcated of the type D—H⋯(A 1,A 2)

trans-Di-μ-iodido-bis­[(3H-1,2-benzodithiole-3-thione)iodidomercury(II)]

The complete molecule of the dinuclear title compound, [Hg2I4(C7H4S3)2], is generated by crystallographic inversion symmetry. The complex has a dimeric structure in which each HgII ion adopts a tetra­hedral geometry and is coordinated by two bridging I atoms, one terminal iodide ion and one thio­carbonyl S atom (C=S) of the ligand. The square plane formed by the Hg and I atoms and their symmetry counterparts makes a dihedral angle of 89.66 (3)° with the DDT plane. There is no classical hydrogen bonding, but weak S⋯S inter­actions of 3.4452 (7) and 3.6859 (7) Å maintain the cohesion of the crystal structure

3-Carboxyanilinium hemioxalate

In the title compound, C7H8NO2+·0.5C2O42−, the asymmetric unit consists of an 3-carboxyanilinium cation, and one-half of an oxalate anion, which lies on a twofold rotation axis. The crystal packing is consolidated by intermolecular N—H...O and O—H...O hydrogen bonds. The structure is built from infinite chains of cations and oxalate anions extending parallel to the b and c axes. The crystal studied was a non-merohedral twin. The ratio of the twin components refined to 0.335 (3):0.665 (3)

Crystal structure, thermal and fluorescence properties of 2,2′:6′,2′′-terpyridine-1,1′,1′′-triium tetrachloridonickelate(II) chloride

International audienceThe title compound, (C15H14N3)[NiCl4]Cl, comprises an NiII cation tetrahedrally coordinated by four chloride anions, a non-coordinating chloride anion and an essentially planar terpyridinium trication (tpyH33+), in which the central pyridinium ring forms dihedral angles of 5.7 (2) and 6.0 (2)degrees with the peripheral pyridinium rings. Three inter-species N-H...Cl hydrogen bonds are formed with the Cl- anion, which also forms a link between the (tpyH33+) cations through an aromatic C-H...Cl interaction, forming a zigzag chain extending along the 21 (b) screw axis. Two of the anionic Cl atoms of the [NiCl4]2- anions form Ni-Cl...[pi] interactions with separate pyridinium rings [Ni...Cg = 3.669 (3) and 3.916 (4) A]. In the crystal, successive undulating inorganic and organic layers are formed, extending across the (100) plane. Thermogravimetric and differential thermal analysis (TGA/DTA) indicate that the compound starts to decompose at 313 K and may be a candidate for use as a blue-light luminescent material

Bis(azido-κN)bis[4-(dimethylamino)pyridine-κN]zinc

In the title complex, [Zn(N3)2(C7H10N2)2], the ZnII atom is coordinated by two N atoms from two 4-(dimethylamino)pyridine (DMAP) ligands and by two N atoms from two azide anions in a distorted tetrahedral coordination geometry. In the crystal, weak C—H...N hydrogen bonds between the DMAP and azide ligands link these discrete complex molecules into a three-dimensional supramolecular network

catena-Poly[[bis[4-(dimethylamino)pyridine-κN1]cobalt(II)]-di-μ-azido-κ4N1:N3]

The title layered polymer, [Co(N3)2(C7H10N2)2]n, contains CoII, azide and 4-(dimethylamino)pyridine (4-DMAP) species with site symmetries m2m, 2 and m, respectively. The Co2+ ion adopts an octahedral coordination geometry in which four N atoms from azide ligands lie in the equatorial plane and two 4-DMAP N atoms occupy the axial positions. The CoII atoms are connected by two bridging azide ligands, resulting in a chain parallel to the c axis