Redetermination of guaninium chloride dihydrate

The low-temperature redetermination of guaninium chloride dihydrate, C₅H₆N₅O⁺·Cl^-·2H₂O, obtained as part of an experimental polymorph screen on guanine, is reported here.

Redetermination of adeninium di­chloride: the question of centrosymmetry

The low-temperature redetermination of adeninium(2+) dichloride, C₅H₇N₅²⁺·2Cl⁻, obtained as part of an experimental polymorph screen on adenine, is reported here. The crystal structure is shown to be centrosymmetric. Cations and anions are connected through N—H...N and N—H...Cl hydrogen bonds [N...N = 2.899 (2) Å and N...Cl = 3.0274 (14)–3.5155 (16) Å] to form sheets perpendicular to the b axis.

A low-temperature determination of butyramide

The low-temperature structure determination of butyramide, C₄H₉NO, obtained as part of a experimental polymorph screen on adenine, is reported here. Each molecule takes part in four hydrogen bonds to form a three-dimensional ribbon structure.

A low-temperature determination of triethyl­ene­diaminium dichloride dihydrate

The structure determination at 150 K of triethyl­ene­diaminium dichloride dihydrate (also know as 1,4-diaza­onia­bicyclo­[2.2.2]octa­ne dichloride dihydrate), C₆H₁₄N₂²⁺·2Cl⁻·2H₂O, obtained as part of an experimental polymorph screen on guanine, is reported here. The packing consists of a hydrogen-bonded chain structure, with one of the water mol­ecules of crystallization involved in weak O—H...Cl contacts.