Theoretical investigation of structure, phosphorescence and static/dynamic nonlinear optical properties of cycloplatinated(II) complexes bearing Pt(ppy)(acac) derivatives

This paper studies the structural, electronic, optical and static/dynamic nonlinear optical properties of a series of cyclometalated platinum complexes, Pt(R-ppy)(acac-C 6 H 4 -R') (Pt-1, Pt-2, Pt-3 and Pt-4), where R = dF(CF 3 ) and R' = I or tert-butyl using DFT and TD‑DFT methods. The influence of fluorination of the ppy ligand and substitution of iodide with a tert-butyl group was investigated to assess their effects on the photophysical and electronic characteristics. The fluorinated complexes show lower frontier orbital energies and stronger charge transfer transitions, while tert-butyl substitution modifies local electron density. The simulated spectra closely match experimental data, accurately replicating vibronic structures and emission patterns. These results demonstrate that subtle structural modifications can precisely adjust energy levels, luminescence and nonlinear optical behavior, providing meaningful insights for the design of advanced platinum-based photonic materials.