Bis(4-ethoxy­anilinium) sulfate trihydrate

The structure of the title compound, 2C8H12NO+·SO4 2−·3H2O, consists of organic layers, water mol­ecules and SO4 2− anions which lie within the organic layers. In the crystal, inter­molecular N—H⋯O, N—H⋯S O—H⋯O and O—H⋯S hydrogen bonds, some of which are bifurcated, stabilize the structure

4-Acetyl­pyridinium hydrogen sulfate

The crystal structure of the title compound, C7H8NO+·HSO4 −, consists of O—H⋯Ohydrogen-bonded extended chains of hydrogen sulfate anions. Each hydrogen sulfate anion is furthermore connected to one 4-acetyl­pyridinium cation via a hydrogen bond of the N—H⋯O type

4-Ethoxy­anilinium perchlorate

In the title compound, C8H12NO+·ClO4 −, there are strong hydrogen bonds between the ammonium groups and the perchlorate O atoms

4-Hy­droxy­anilinium perchlorate dihydrate

In the crystal structure of the title compound, C6H8NO+·ClO4 −·2H2O, inter­molecular N—H⋯O and O—H⋯O hydrogen bonds occur. The protonated amine cations and the perchlorate anions are linked through the water mol­ecules, and the hy­droxy groups of the cations and the anions are linked through the water mol­ecules. The cations are connected to the perchlorate anions via inter­molecular N—H⋯O hydrogen bonds. In addition, the crystal structure exhibits weak inter­molecular C—H⋯π inter­actions

4-Acetyl­pyridinium perchlorate

In the crystal of the title mol­ecular salt, C7H8NO+·ClO4 −, the ions are linked by N—H⋯O hydrogen bonds, resulting in chains propagating in [010]. The packing is reinforced by C—H⋯O inter­actions

1-[(Z)-2-Cyano-2-(2-pyrid­yl)vin­yl]­ferrocene

In the title compound, [Fe(C5H5)(C13H9N2)], the dihedral angle between the substituted cyclo­penta­dienyl plane and the plane of the pyridine ring is 8.43 (14)°. The double bond adopts a Z configuration. In the crystal structure, weak C—H⋯N inter­actions link the molecules into a zigzag chain. A weak intramolecular C—H⋯N hydrogen bond is also present

4-Iodo­anilinium nitrate

In the title compound, C6H7IN+·NO3 −, π–π stacking inter­actions [centroid–centroid distances = 4.014 (4) and 4.029 (4) Å] stabilize the crystal structure and strong N—H⋯O and N—H⋯N hydrogen bonds link the cations and anions into zigzag chains running parallel to the c axis. The asymmetric unit contains two unique cations and anion