Synthesis and crystal structure of the coordination compound of cadmium diiodide monohydrate with quinoxaline

The coordination compound [CdI 2 (Quinox) 2 (H 2 O)] has been synthesized by the reaction between CdI 2 and quinoxaline (Quinox, C 8 H 6 N 2 ) in a water–ethanol (1: 5) solution, and its crystal structure has been determined. Crystals are orthorhombic, space group Pnma , a = 13.069(1) Å, b = 15.218(1) Å, c = 9.423(1) Å, V = 1874.0(3) Å 3 , ρ calcd = 2.284 g/cm 3 , Z = 4. The cadmium atom is located in the plane m and has a distorted trigonal bipyramidal coordination; two crystallographically nonequivalent iodine atoms and the O(H 2 O) atom are in the equatorial plane, and the two nitrogen atoms of two symmetric Quinox ligands are in the axial vertices (Cd(1)–N(1), 2.490(3) × 2 Å; Cd(1)–I(1), 2.7533(6) Å; Cd(1)–I(2), 2.7280(7) Å). The angles at the cadmium atom are 157.1 (2)° between the axial nitrogen atoms and 107.9(1)°–130.8(1)° between the equatorial atoms (maximum value corresponds to the ICdI angle). The complexes are linked into supramolecular strips via O–H…N hydrogen bonds.