Synthesis, Characterization, Crystal Structure, Hirshfeld Surface Analysis and Spectroscopic Properties of bis(5-aminoisophthalato)bispicolinecopper (II)

Abstract

The 2D coordination polymer of Cu(II), [Cu(5-aip) (3-pic)<inf>2</inf>]<inf>n</inf> (5-aip = 5-aminoisophthalato, 3-pic = 3-picoline) was characterized by elemental analysis, FT-IR and UV–Vis spectroscopy and single crystal XRD techniques. The X-ray single crystal data revealed that the polymeric coordination complex crystallizes in the monoclinic system with P2<inf>1</inf>/n space group and Cu(II) ion has five (square pyramidal) coordination number. X-ray diffraction analysis show that Cu(II) has a distorted square pyramidal geometry with τ = (175.75–160.0)/60) = 0.2625. Hirshfeld surface analysis was carried out, which reveals the nature of intermolecular contacts, the fingerprint plots and molecular surface contours (d<inf>norm</inf>, d<inf>i</inf> and d<inf>e</inf>) provide the information about the percentage contributions [H⋯H (40.5%), C⋯H (29.2%), Cu⋯O (4.7%), N⋯H (4.9%), N⋯O (1.5%) and O⋯H (17.4%)] and revealed them major and minor contributions of the bond interactions for [Cu(5-aip) (3-pic)<inf>2</inf>]<inf>n</inf> complex. According to UV–Vis spectrum, d-d transition observed at 712 nm (ε = 65 dm3mol−1cm−1) which is assigned to the d<inf>z</inf> 2 (a<inf>1</inf>)→d<inf>x</inf> 2 <inf>-y</inf> 2 (b<inf>1</inf>) transition. Thermogravimetric analysis was carried out to fallow the thermal stability of the complex. © 2020 Elsevier B.V.