Cu(II) and Zn(II) Complexes with an <i>N</i>- and <i>O</i>-Donor Ligand: Structural Characterization, Jahn-Teller Effect and Fluorescence

Cu(II) and Zn(II) salts react with 5-(1H-benzotriazol-1-ylmethyl)isophthalic acid (H₂L) under hydrothermal conditions to yield two new complexes [Cu(L)(DMF)(H₂O)] (1) and [Zn(L)] (2) [DMF = N,N-dimethylformamide], which have been characterized by single-crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. As a result, 1 shows a chain structure, further linked together by hydrogen bonding and π–π interactions to give rise to a 3D supramolecular framework. Complex 2 is a binodal (3,6)-connected 2D kgd network with (4³)₂(4⁶.6⁶.8³) topology. The influential factors of synthetic strategies on coordination modes of the ligand and structures of the resulting complexes are embodied in the study. Significantly, 1 has structural features consistent with the Jahn-Teller effect. Furthermore, the fluorescence properties of 2 were preliminarily investigated.