RESUMO
The structures of three isomorphous compounds, namely bis(2,6-dibromopyridinium) tetrabromidocuprate(II) dihydrate, (C(5)H(4)Br(2)N)(2)[CuBr(4)].2H(2)O, bis(2,6-dibromopyridinium) tetrabromidocadmate(II) dihydrate, (C(5)H(4)Br(2)N)(2)[CdBr(4)].2H(2)O, and bis(2,6-dibromopyridinium) tetrabromidomercurate(II) dihydrate, (C(5)H(4)Br(2)N)(2)[HgBr(4)].2H(2)O, show a crystal supramolecularity represented by M-Br...H-O-H...Br-M intermolecular interactions along with (pi)N-H...OH(2) hydrogen-bonding interactions forming layers connected via aryl-aryl face-to-face stacking of cations, leading to a three-dimensional network. The anions have significantly distorted tetrahedral geometry and crystallographic C(2) symmetry. The stability of this crystal lattice is evidenced by the crystallization of a whole series of isomorphous compounds.
RESUMO
In the structural motifs of two isomorphous triclinic salts, (C5H6Br2N3)2[MBr4] (M = Cd(II) and Mn(II)), each [MBr4]2- anion interacts with eight surrounding 2,6-diamino-3,5-dibromopyridinium cations through intermolecular C/N-H...Br and Br...Br interactions, leading to a three-dimensional framework structure. The cations show a minor degree of pi-pi stacking, adding extra stability to the three-dimensional architecture.
RESUMO
In the title compound, C(5)H(3)Br(2)N, C-Hâ¯N hydrogen-bonding inter-actions and Brâ¯Br inter-actions [3.9418â (3) and 3.8986â (3)â Å] connect the mol-ecules into planar sheets stacked perpendicular to the b axis. In addition, pyrid-yl-pyridyl inter-sheet π-π stacking inter-actions [centroid-centroid distance = 4.12â (1)â Å] result in a three-dimensional network.
RESUMO
The asymmetric unit of the title compound, (C(5)H(6)Br(2)N(3))(2)[SnBr(6)], contains one cation and one half-anion in which the Sn atom is located on a crystallographic centre of inversion and is in a quasi-octa-hedral geometry. The crystal structure is assembled via hydrogen-bonding inter-actions of two kinds, N(pyridine/amine)-Hâ¯Br-Sn, along with C-Brâ¯Br-Sn interactions [3.4925â (19)â Å]. The cations are involved in π-π stacking, which adds an extra supra-molecularity as it presents a strong case of offset-face-to-face motifs [centroid-centroid distance = 3.577â (3)â Å]. The inter-molecular hydrogen bonds, short Brâ¯Br inter-actions and π-π stacking result in the formation of a three-dimensional supra-molecular architecture.
RESUMO
In the crystal structure of the title compound, (C(7)H(10)N)(2)[CoBr(4)], the [CoBr(4)](2-) anion is connected to two cations through N-Hâ¯Br and H(2)C-Hâ¯Br hydrogen bonds to form two-dimensional cation-anion-cation layers normal to the crystallographic b axis. Inter-actions of the π-π type are absent between cations in the stacks [centroid-centroid separation = 5.01â (5)â Å]. Significant inter-molecular Br-aryl inter-actions are present in the structure, especially an unusually short Br-ring centroid inter-action of 3.78â (1)â Å. The coordination geometry of the anion is approximately tetrahedral and a twofold rotation axis passes through the Co atom.
RESUMO
In the crystal structure of the title compound, (C(6)H(9)N(2))(2)[CuBr(4)], the geometry around the Cu atom is inter-mediate between tetra-hedral (T(d)) and square planar (D(4h)). Each [CuBr(4)](2-) anion is connected non-symmetrically to four surrounding cations through N-Hâ¯X (pyridine and amine proton) hydrogen bonds, forming chains of the ladder-type running parallel to the crystallographic b axis. These layers are further connected by means of offset face-to-face inter-actions (parallel to the a axis), giving a three-dimensional network. Cation π-π stacking [centroid separations of 3.69â (9) and 3.71â (1)â Å] and Brâ¯aryl inter-actions [3.72â (2) and 4.04â (6)â Å] are present in the crystal structure. There are no inter-molecular Brâ¯Br inter-actions.
RESUMO
The asymmetric unit of the title compound, (C(5)H(5)BrN)(2)[SnBr(6)], contains one cation and one half-anion. The [SnBr(6)](2-) anion is located on an inversion center and forms a quasi-regular octa-hedral arrangement. The crystal structure consists of two-dimensional supra-molecular layers assembled via hydrogen-bonding inter-actions of N-Hâ¯Br-Sn [Dâ¯A = 3.375â (13)-3.562â (13)â Å and D-Hâ¯A = 127-142°, along with C-Brâ¯Br synthons [3.667â (2) and 3.778â (3)â Å]. These layers are parallel to the bc plane and built up from anions inter-acting extensively with the six surrounding cations.
RESUMO
The asymmetric unit of the title compound, (C(5)H(8)N(2))[HgBr(4)]·H(2)O, consists of one cation, one anion and one water mol-ecule. The anion exhibits a distorted tetra-hedral arrangement about the Hg atom. The crystal structure contains alternating sheets of cations (in the ac plane) and stacks of anions. Several strong hydrogen-bonding inter-actions (pyN-Hâ¯Br and C-Hâ¯Br; py is pyridine), along with O-Hâ¯Br inter-actions, connect the sheets of cations to the stacks of anions. Cation-cation π-π stacking is also present (Câ¯C distances in the range 3.424-3.865â Å). The shortest Brâ¯Br distance is 3.9527â (9)â Å.
RESUMO
The asymmetric unit of the title compound, (C(6)H(9)N(2))(2)[CuCl(4)], consists of one cation and one half-anion, bis-ected by a twofold rotation axis through the metal center. The anion exhibits a geometry that is inter-mediate between a T(d) and D(4h) arrangement about the Cu atom. The crystal structure contains chains of cations alternating with stacks of anions. The cationic groups inter-act via offset face-to-face π-π stacking, forming chains running along the c axis. The anion stacks are parallel to the cation chains, with no significant inter- nor intra-stack Clâ¯Cl inter-actions. There are several anion-cation hydrogen-bonding inter-actions of the (N-H)(pyridine)â¯Cl and (N-H)(amino)â¯Cl types, connecting the chains of cations to the stacks of anions. Both the N-Hâ¯Cl and π-π stacking inter-actions [centroid-centroid distances 3.61â (8) and 3.92â (2)â Å] contribute to the formation of a three-dimensional supra-molecular architecture.