Photoluminescence and nonlinear optical properties of Cu, Zn, Co, and Ni complexes based on 3,4,5-trimethoxybenzoic acid and nicotinamide
Synthetic Metals, cilt.320, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 320
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.synthmet.2026.118228
- Dergi Adı: Synthetic Metals
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC
- Anahtar Kelimeler: Defect states, Metal-organic complexes, Nonlinear Absorption, Open Aperture Z-scan, Optical Limiting
- Ankara Üniversitesi Adresli: Evet
Özet
Metal–organic complexes are promising candidates for nonlinear optical (NLO) applications owing to their tunable electronic structures and strong charge-transfer interactions. In this work, the photoluminescence (PL) and nonlinear absorption (NA) properties of Cu-, Zn-, Co-, and Ni-based nicotinamide complexes were systematically investigated in chloroform (CHCl3) solutions and in poly(methyl methacrylate) (PMMA) thin films. In addition to ligand substitution effects, the present work systematically investigates, for the first time, the influence of nitro-containing additives on the absorption and photoluminescence behavior of MbN-based metal complexes. Optical characterization revealed that the complexes exhibit distinct absorption and emission features depending on the coordinated metal center and surrounding medium. When embedded in PMMA matrices, the materials showed effective transition energies in the range of 5.32–5.42 eV and broad emission bands in the visible region. Open-aperture Z-scan measurements at 532 nm with 4 ns laser pulses demonstrated pronounced nonlinear absorption behavior dominated by two-photon and excited-state absorption processes. Among the investigated systems, the CuMbN/PMMA complex exhibited the strongest nonlinear optical response with a nonlinear absorption coefficient of 7.73 × 10⁻⁶ m/W and an optical limiting threshold of 5.29 mJ/cm². Compared with our previously reported HbN-based analogues, the methoxy-substituted MbN complexes demonstrate modified charge-transfer interactions and nonlinear absorption behavior. These results demonstrate that PMMA-embedded metal–nicotinamide complexes combine tunable photophysical properties with efficient nonlinear absorption, highlighting their potential as promising materials for optical limiting and photonic protection applications.