metal-organic compounds
Open access
The asymmetric unit of the title salt, (C5H7N2)2[Cr2O7], contains four independent cations and two independent dichromate anions. The crystal structure consists of discrete dichromate anions with an eclipsed conformation stacked in layers parallel to (010) at y = 1/4 and y = 3/4. These layers are linked via 4-aminopyridinium cations by N—HO and weak C—HO hydrogen bonds, forming a three-dimensional supramolecular network. In addition, π–π interactions are present in this structure; the shortest distance separating mean planes through 4-aminopyridinium cations is 3.679 (6) Å.
organic compounds
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The asymmetric unit of the title salt, C8H14N22+·2NO3−, contains two independent dications and four independent nitrate anions. The crystal structure consists of discrete nitrate ions, three of which stack in layers parallel to (001) at z = 0 and 0.5. These layers are connected via m-xylylenediaminium dications. The fourth anion is sandwiched by the two independent organic cations in the asymmetric unit. In the crystal, the ions are connected by a large number of bifurcated and non-bifurcated N—HO(O) hydrogen bonds, forming sheets parallel to (100). These sheets are connected by C—HO hydrogen bonds, forming a three-dimensional network.
organic compounds
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The asymmetric unit of the title salt [systematic name: 2-(3,4-dihydroxyphenyl)ethanaminium nitrate], C8H12NO2+·NO3−, contains two independent cations and two independent nitrate anions. The crystal structure consists of discrete nitrate ions stacked in layers parallel to (010). These layers are linked via the dopaminium cations by O—HO, N—HO and weak C—HO hydrogen bonds, forming a three-dimensional supramolecular network.
organic compounds
Open access
In the structure of the title salt, C6H16N22+·2NO3−, the cations are connected to the anions through bifurcated N—H(O,O) and weak C—HO hydrogen bonds, generating corrugated layers parallel to the (100) plane. The organic cation is centrosymmetric and the diprotonated piperazine ring adopts a chair conformation, with the methyl groups occupying equatorial positions.