Nonlinear optical functionalized Cu( <scp>ii</scp> ) coordination complexes with chiral ligands: design, structural elucidation, and theoretical investigation
Nagesh Manurkar, Mubashar Ilyas, Faiza Arshad, Prasanna J. Patil, Qamar‐un‐Nisa Tariq, Shahzad Alam Khan, Maroof Ahmad Khan, Hui Li
Abstract
space group and the central Cu(II) has a distorted square-pyramidal geometry, and noncentrosymmetric packing, which are advantageous for improving nonlinear optical (NLO) properties. Complementary computational analyses, including density functional theory (DFT) calculations, emphasized the significant impact of halogen substitution on the electronic characteristics of both the ligands and their copper complexes. These substitutions from H, F, Cl, Br, and I significantly reduced the HOMO-LUMO gaps, increasing the electron density and improving charge transfer characteristics gradually and respectively. Comparing with ligands, their copper complexes exhibited enhanced linear and nonlinear optical properties, among which complex-4 shows the most significant NLO performance, particularly in second-harmonic generation and electro-optic responses. The relationship between the structure and NLO properties has been understood based on experimental and computational investigations. This work can help in designing functionalized coordination complexes with enhanced NLO properties.