A second solvatomorph of poly[[μ-,'-(1,3,5-oxadiazinane-3,5-di-yl)bis-(carbamoyl-methano-ato)]nickel(II)dipotassium]: crystal structure, Hirshfeld surface analysis and semi-empirical geometry optimization.

The title compound, poly[tri-aqua-bis-[μ-,'-(1,3,5-oxadiazinane-3,5-di-yl)bis(carbamoyl-methano-ato)]dinickel(II)tetra-potassium], [KNi(CHNO)(HO)] , is a second solvatomorph of poly[(μ-,'-(1,3,5-oxadiazinane-3,5-di-yl)bis-(carbamoyl-methano-ato)nickel(II)dipotassium] reported previously [Plutenko (2021 ▸). E, 298-304]. The asymmetric unit of the title compound includes two structurally independent complex anions [Ni(CHNO)], which exhibit an L-shaped geometry and consist of two almost flat fragments perpendicular to one another: the 1,3,5-oxadiazinane fragment and the fragment including other atoms of the anion. The central Ni atom is in a square-planar NO coordination arrangement formed by two amide N and two carboxyl-ate O atoms. In the crystal, the title compound forms a layered structure in which layers of negatively charged complex anions and positively charged potassium cations are stacked along the -axis direction. The polymeric framework is stabilized by a system of hydrogen-bonding inter-actions in which the water mol-ecules act as donors and the carb-oxy-lic, amide and water O atoms act as acceptors.