Syntheses and Characterizations of Three New Coordination Compounds: [M(C9NH7)4(SCN)2] (M = Zn, Cd) and [Zn(C9NH7)2(SCN)2] With a Pseudo-merohedral Twinning Structure

The reactions of Cd(NO3)2, ZnSO4, KSCN, and isoquinoline under hydrothermal conditions produced three new coordination complexes, i.e., [Zn(C9NH7)4(SCN)2] (I), [Cd(C9NH7)4(SCN)2] (II), and [Zn(C9NH7)2(SCN)2] (III). Investigation of single-crystal X-ray diffraction shows that complexes (I) and (II) are isostructural and crystallize in tetragonal space group P42/n, and complex (III) crystallizes in monoclinic space group P2/n. In complexes (I) and (II), ZnII and CdII cations are surrounded by six N atoms, while ZnII cations in complex (III) are surrounded by four N atoms. In complex (III), the intensity statistics revealed the presence of pseudo-merohedral twinning.