Push–pull D–π-Ru–π-A chromophores: synthesis and electrochemical, photophysical and second-order nonlinear optical properties. Issue 11 (21st February 2018)

• Record Type: Journal Article
• Authors: Durand, Raphaël J.; Gauthier, Sébastien; Achelle, Sylvain; Groizard, Thomas; Kahlal, Samia; Saillard, Jean-Yves; Barsella, Alberto; Le Poul, Nicolas; Le Guen, Françoise Robin
• Is Part Of: Dalton transactions. Volume 47:Issue 11(2018)
• Page Start: 3965
• Page End: 3975
• Publication Date: 2018-02-21
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c8dt00093j
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : This work describes the synthesis and electrochemical, photophysical and 2nd order NLO properties of a series of dipolar Ru(ii ) dialkynyl complexes. Abstract : The present work describes the one-pot synthesis and electrochemical, photophysical and second-order nonlinear optical (NLO) properties of a series of dipolar π-delocalized Ru(ii ) dialkynyl complexes. The eight new asymmetrical D–π-Ru–π-A push–pull chromophores incorporate pyranylidene ligands as pro-aromatic donor groups (D) and formaldehyde, indane-1, 3-dione, pyrimidine or pyrimidinium as electron-attracting groups (A) separated by ruthenium bis-acetylide fragments and π-conjugated linkers. The second-order nonlinear optical (NLO) properties of all eight complexes were determined by the Electric-Field-Induced Second Harmonic generation (EFISH) technique (operating at 1907 nm), and were compared to those of their purely organic analogs. All investigated compounds (organic and organometallic) exhibited positive μβ values, which dramatically increased for the complexes due to the presence of ruthenium in the π-conjugated core. The second-order NLO response could also be easily modulated by changing the nature of alkynyl substituents. The most promising ruthenium complexes7 and8 of the series with the pyrimidinium fragment displayed μβ values of 14 000 × 10 −48 esu. The effect of structural modifications on the redox and spectroscopic properties of the complexes was also studied. The intramolecular charge transfer (ICT) occurring through the ruthenium center of the push–pull σ-dialkynyl complexes was investigated by combining experimental and theoretical data.