Synthesis, crystal structure and Hirshfeld surface analysis of bis-[2-amino-5-(ethyl-sulfan-yl)-1,3,4-thia-diazol-3-ium] bis-(perchlorato-κO)bis-(picolinato-κ(2) N,O)copper(II).

In the title coordination complex, (C(4)H(8)N(3)S(2))(2)[Cu(C(6)H(4)NO(2))(2)(ClO(4))(2)], the Cu(II) center exhibits a distorted octa-hedral geometry with an equatorial plane formed by two bidentate picolinato ligands and axial coordination from two perchlorate anions, consistent with a Jahn-Teller distortion. The crystal structure is further consolidated by a network of hydrogen bonds involving the thia-diazole-based cations, which reside in the outer coordination sphere in a unique protonated state. Hirshfeld surface analysis reveals that O⋯H/H⋯O contacts dominate the inter-molecular inter-actions, contributing significantly to the crystal packing.