Tetrakis(2-amino-5-methyl-1,3,4-thia-diazole-N-3)chlorocopper(II) chloridemonohydrate and tetrakis(2-amino-5ethyl-1,3,4-thiadiazole-N-3)chlorocopper(II) chloride

The structures of the title compounds, [CuCl(C3H5N3S)(4)]Cl radical anion H 2O, (I), and [CuCl(C4H7N3S)(4)]Cl, (II), comprise square-pyramidal Cu centr es with four N-bound organic ligands filling the base positions, a Cl atom in the apical position and a Cl- as a free counter-ion. The cation and free chloride ion in (II) have fourfold crystallographic symmetry. Hydrogen-bon ding associations from the 2-amino H atoms dominate both structures, with t he principal acceptors being the chlorides, although in (I), the N4 atoms a re also involved. Furthermore, (I) is a hydrate, with the water molecule pa rticipating in the hydrogen-bonding network.