The twinned crystal structure of [4,4′-bipyridine]-1,1′-diium hexachloridostannate(IV), C10H10N2SnCl6

C10H10N2SnCl6, monoclinic, I2/a (no. 15), a = 7.4941(3) Å, b = 12.8731(4) Å, c = 15.8688(5) Å, β = 93.042(3)°, Z = 4, V = 1528.73(9) Å3, R gt (F) = 0.0264, wR ref = 0.0485, T = 100 K.

Crystal structure of 4-(4′-(pyridin-4-yl)-[1,1′-biphenyl]-4-yl)pyridin-1-ium 2-carboxy-4-(3,5-dicarboxyphenoxy)benzoate hydrate, C38H28N2O10

C38H28N2O10, triclinic, P1̄ (no. 2), a = 11.3207(6) Å, b = 11.9296(6) Å, c = 13.6079(8) Å, α = 115.195(5)°, β = 103.259(5)°, γ = 97.356(4)°, V = 1564.58(15) Å3, Z = 2, R gt(F) = 0.0537, wR ref(F 2) = 0.1286, T = 293(2) K.

The crystal structure of 4,4′-bipyridinium bis(3-carboxy-2-nitrobenzoate) tetrahydrate, C13H13N2O8

C13H13N2O8, triclinic, P1̄ (no. 2), a = 7.8590(6) Å, b = 9.3108(8) Å, c = 11.0816(8) Å, α = 66.950(3)°, β = 71.558(3)°, γ = 77.203(4)°, V = 703.38(10) Å3, Z = 2, Rgt(F) = 0.0389, wRref(F2) = 0.1075, T = 149(2) K.

Chain length effect in the functionalization of polyoxometalates with α,ω-alkyldiphosphonates

Varying the alkylene tethers in hybrids of polyoxometalates and α,ω-alkyldiphosphonates, even just by a single methylene group, has met with strong structural and magnetic responses.

Hydrogen bonds and van der Waals forces as tools for the construction of a herringbone pattern in the crystal structure of hexane-1,6-diaminium hexane-1,6-diyl bis-(hydrogen phospho-nate)

The asymmetric unit of the title salt, [H3N(CH2)6NH3][(HO)O2P(CH2)6PO2(OH)], consists of one half of a hexane-1,6-diaminium dication and one half of a hexane-1,6-diyl bis-(hydrogen phospho-nate) dianion. Both are located around different centres of inversion (Wyckoff sites: 2a and 2d) of the space group P21/c. The shape of the hexane-1,6-diaminium cation is best described as a double hook. Both aminium groups as well as the two attached CH2 groups are turned out from the plane of the central four C atoms. In contrast, all six C atoms of the dianion are almost in a plane. The hydrogen phospho-nate (-PO3H) groups of the anions and the aminium groups of the cations form two-dimensional O-H⋯ and O-H⋯N hydrogen-bonded networks parallel to the ac plane, built up from ten-membered and twelve-membered ring motifs with graph-set descriptors R33(10) and R54(12), respectively. These networks are linked by the alkyl-ene chains of the anions and cations. The resulting three-dimensional network shows a herringbone pattern, which resembles the parent structures 1,6-di-amino-hexane and hexane-1,6-di-phospho-nic acid.

Hydrogen bonding, π-π stacking and van der Waals forces-dominated layered regions in the crystal structure of 4-amino-pyridinium hydrogen (9-phosphono-non-yl)phospho-nate

The asymmetric unit of the title mol-ecular salt, [C5H7N2+][(HO)2OP(CH2)9PO2(OH)-], consists of one 4-amino-pyridinium cation and one hydrogen (9-phos-phono-non-yl)phospho-nate anion, both in general positions. As expected, the 4-amino-pyridinium moieties are protonated exclusively at their endocyclic nitro-gen atom due to a mesomeric stabilization by the imine form which would not be given in the corresponding double-protonated dicationic species. In the crystal, the phosphonyl (-PO3H2) and hydrogen phospho-nate (-PO3H) groups of the anions form two-dimensional O-H⋯O hydrogen-bonded networks in the ab plane built from 24-membered hydrogen-bonded ring motifs with the graph-set descriptor R66(24). These networks are pairwise linked by the anions' alkyl-ene chains. The 4-amino-pyridinium cations are stacked in parallel displaced face-to-face arrangements and connect neighboring anionic substructures via medium-strong charge-supported N-H⋯O hydrogen bonds along the c axis. The resulting three-dimensional hydrogen-bonded network shows clearly separated hydro-philic and hydro-phobic structural domains.