Bis( N , N -di-ethyl-dithio-carbamato-κ 2 S , S ')(3-hy-droxy-pyridine-κ N )zinc and bis-[ N -(2-hy-droxy-eth-yl)- N -methyldithio-carbamato-κ 2 S , S '](3-hy-droxy-pyridine-κ N )zinc: crystal structures and Hirshfeld surface analysis

The common feature of the mol-ecular structures of the title compounds, [Zn(C H NS ) (C H NO)], (I), and [Zn(C H NOS ) (C H NO)], (II), are NS donor sets derived from -bound hy-droxy-pyridyl ligands and asymmetrically chelating di-thio-carbamate ligands. The resulting coordination geometries are highly distorted, being inter-mediate between square pyramidal and trigonal bipyramidal for both independent mol-ecules comprising the asymmetric unit of (I), and significantly closer towards square pyramidal in (II). The key feature of the mol-ecular packing in (I) is the formation of centrosymmetric, dimeric aggregates sustained by pairs of hy-droxy-O-H⋯S(di-thio-carbamate) hydrogen bonds. The aggregates are connected into a three-dimensional architecture by methyl-ene-C-H⋯O(hy-droxy) and methyl-C-H⋯π(chelate) inter-actions. With greater hydrogen-bonding potential, supra-molecular chains along the axis are formed in the crystal of (II), sustained by hy-droxy-O-H⋯O(hy-droxy) hydrogen bonds, with ethyl-hydroxy and pyridyl-hydroxy groups as the donors, along with ethyl-hydroxy-O-H⋯S(di-thio-carbamate) hydrogen bonds. Chains are connected into layers in the plane by methyl-ene-C-H⋯π(chelate) inter-actions and these stack along the axis, with no directional inter-actions between them. An analysis of the Hirshfeld surfaces clearly distinguished the independent mol-ecules of (I) and reveals the importance of the C-H⋯π(chelate) inter-actions in the packing of both (I) and (II).