4‐Iodo‐N‐(2‐nitro­phenyl­sulfanyl)­aniline: π‐stacked sheets generated by a combination of N—H⃛O and C—H⃛O hydrogen bonds

Molecules of the title compound, C₁₂H₉IN₂O₂S, are linked by one N—H⃛O hydrogen bond [H⃛O = 2.16 Å, N⃛O = 2.935 (4) Å and N—H⃛O 147°] and two C—H⃛O hydrogen bonds [H⃛O both 2.49 Å, C⃛O = 3.231 (5) and 3.220 (5) Å, and C—H⃛O = 135 and 134°] into sheets which themselves are weakly linked by an aromatic π–π‐stacking interaction between iodinated rings in centrosymmetrically related mole­cules. There are no iodo–nitro interactions.     

6,6′‐Di­methoxy‐2,2′‐[(1R,2R)‐cyclo­hexane‐1,2‐diyl­bis­(nitrilo­methyl­idyne)]­diphenol: three C—H⃛O hydrogen bonds generate a three‐dimensional framework

Molecules of the title compound, alternatively called (R,R)‐N,N′‐bis(3‐methoxysalicylidene)‐trans‐cyclohexane‐1,2‐diamine, C₂₂H₂₆N₂O₄, contain two intramolecular O—H⃛N hydrogen bonds and adopt a conformation with approximate twofold rotational symmetry. The mol­ecules are linked by three C—H⃛O hydrogen bonds [H⃛O = 2.45–2.55 Å, C⃛O = 3.329 (2)–3.398 (2) Å and C—H⃛O = 142–172°] into a continuous framework.     

Bis­[6‐amino‐3‐methyl‐5‐nitro­so­pyrimidine‐2,4(1H,3H)‐dionato]­di­aqua­zinc(II) dihydrate,redetermined at 120 K: a three‐dimensional hydrogen‐bonded framework

The title compound, whose structure has been redetermined at 120 K, contains almost centrosymmetric trans‐[Zn(C₅H₅N₄O₃)₂(H₂O)₂]·2H₂O units, together with two uncoordinated water mol­ecules. An extensive series of O—H⃛O, O—H⃛N and N—H⃛O hydrogen bonds gives rise to a three‐dimensional framework structure.     

Bilayers in 4‐iodo‐N‐(2‐iodo‐4‐nitrophenyl)benzamide generated by a combination of an N—H⋯O=C hydrogen bond and two independent iodo–nitro interactions

Molecules of the title compound, C₁₃H₈I₂N₂O₃, are linked into C(4) chains by a single N—H⋯O=C hydrogen bond [H⋯O = 2.10 Å, N⋯O = 2.832 (5) Å and N—H⋯O = 140°]. Two independent two‐centre iodo–nitro interactions, both involving the same O atom but different I atoms [I⋯O = 3.205 (3) and 3.400 (3) Å, and C—I⋯O = 160.4 (2) and 155.7 (2)°], link the hydrogen‐bonded chains into bilayers.     

2‐Amino­benzimidazolium O‐ethyl malonate: eight independent N—H⋯O hydrogen bonds generate sheets

The title compound, C₇H₈N₃⁺·C₅H₇O₄⁻, crystallizes with Z′ = 2 in space group P2₁/c; eight independent N—H⋯O hydrogen bonds [H⋯O = 1.75–1.88 Å, N⋯O = 2.699 (2)–2.829 (2) Å and N—H⋯O = 147–179°] link the four inde­pendent ions into sheets.     

rac‐1‐Phenyl­ethyl­ammonium carboxy­methyl­phospho­nate(1–): hydrogen‐bonded anion sheets with pendent cations

In the title compound, C₈H₁₂N⁺·C₂H₄O₅P⁻, the anions are linked by two O—H⋯O hydrogen bonds [H⋯O both 1.75 Å, O⋯O = 2.5781 (15) and 2.5834 (15) Å, and O—H⋯O = 169 and 176°] into sheets built from alternating (8) and (32) rings. Each cation is linked to an anion sheet by three N—H⋯O hydrogen bonds [H⋯O = 1.88–2.04 Å, N⋯O = 2.7603 (16)–2.9334 (17) Å and N—H⋯O = 162–166°], such that all the cations pendent from one face of the sheet are of the R configuration, while all those pendent from the opposite face are of the S configuration.