Abstract
In this study, two Cu2+-doped single crystals, [Cu-0.02(H1.96L)](ClO4)(2) (1) and [Cu-0.91(H0.18L)](ClO4)(2) (2) (L =3,14- diethyl-2,6,13,17-tetraazatricyclo(16.4.0.0(7,12)) docosane), were prepared and characterized by elemental and X-ray crystal structural analyses, along with UV-visible, infrared (IR) and electron paramagnetic resonance (EPR) spectroscopies. The asymmetric units of compounds 1 and 2 contain one half of the molecular dication and one doubly disordered perchlorate anion. The macrocyclic ligand in both the Cu2+-doped compounds adopts the most stable trans-III conformation. The Cu-N bond lengths in the range 2.010 (2)-2.055 (3) angstrom are normal, but the long axial Cu1-O3 bonds of 2.836 (3) and 2.729 (3) A for 1 and 2, respectively, may be due to a combination of the Jahn-Teller effect and strong in-plane ligand field. The crystals are stabilized by hydrogen bonds involving the secondary N-H, the N atoms of the macrocycle, and the O atoms of the perchlorate groups. (C) 2019 Elsevier B.V. All rights reserved.