Crystal Structure, Topological and Hirshfeld Surface Analysis of a Zn(II) Zwitterionic Schiff Base Complex Exhibiting Nonlinear Optical (NLO) Properties Using <i>Z</i>-Scan Technique

Abstract

A mononuclear Zn(II) complex of (Zn(H2L) (CH3OH) Cl2) (1) has been synthesized by using a nonlinear optically active Zwitterionic Schiff base which is 4-((2-hydroxy-3-methoxybenzylidene) amino) benzoic acid (H2L). Complex 1 has been structurally analyzed by FTIR and UV spectroscopy, TGA, Powder-XRD and single crystal X-ray diffraction. X-Ray crystallographic studies revealed Zn(II) complex crystallizes in a P21/c space group and exists in a distorted trigonal bipyramidal geometry (τ = 0.68). The topological analysis of complex 1 showed that the underlying net is characterized by an unknown topological type and point symbol {342.468.510}, and multilevel analysis of complex packing as dimer gives a 18-c uninodal net with unknown topological type and point symbol {348.499.56}. The calculation results of a Hirshfeld surface analysis have been investigated to explore the H-bonding within the crystal. Third-order non-linear properties were also studied, which revealed that the lower input power (5.0 mM) for the material shows full transparency; however, it becomes opaque for higher input power. Such limiting behavior of complex 1 suggests its potential for instrumental protective devices against high laser illuminations.

Keywords

• Zn(II) complex
• zwitterion
• single crystal XRD
• Hirshfeld surface analysis
• third-order NLO