Design and synthesis of heterocycle-based push-pull NLOphores: A comprehensive study of their linear and non-linear optical properties


Karagöllü B., Şengöz T. O., Kayaş H., ERDEN K., ŞAHİN E., ESENTÜRK O., ...Daha Fazla

Dyes and Pigments, cilt.232, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 232
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.dyepig.2024.112469
  • Dergi Adı: Dyes and Pigments
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Charge-transfer, Conjugation, Cycloaddition, Donor-acceptor, NLOphores, Optoelectronics, Z-scan
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Push-pull chromophores, with strong intramolecular charge transfer (ICT), exhibit high ground-state polarization, driving strong NLO responses. The donor and acceptor abilities of the groups in the investigated compounds influence ICT, so the nonlinear response of these compounds was analyzed in relation to their strength. Two different families of NLOphores were synthesized through [2 + 2] cycloaddition-retroelectrocyclizations of heterocycle-based electron-rich alkynes with tetracyanoethylene (TCNE) and tetracyanoquinodimethane (TCNQ). The λmax values of push-pull chromophores, particularly for charge transfer bands, fall within the range of 424–758 nm. The linear and nonlinear optical properties of these NLOphores were subsequently examined through a combination of experimental and theoretical methods. NLO measurements were conducted using a validated custom-made Z-scan device. The nonlinear absorption coefficients range from −1.44 × 10−4 cm.W−1 to −9.90 × 10−4 cm.W−1, while nonlinear refractive indices range from −1.59 × 10−7 cm2. W−1 to −2.26 × 10−6 cm2. W−1. As expected from their molecular structures, the TCNQ products displayed stronger nonlinear responses than the TCNE products.