title: Second-order NLO switches from molecules to polymer films based on photochromic cyclometalated platinum(II) complexes.
abstract: Novel photochromic dithienylethene-based platinum(II) complexes (C^N^N)Pt(C≡C-DTE-C6H4-D) ((C^N^N) = 4,4'-di(n-hexyl)-6-phenyl-2,2'-bipyridine; D = H, NMe2) were prepared and characterized. Their excellent photochromic properties allow the photoinduced switching of their second-order nonlinear optical properties in solution, as measured by the EFISH technique, due to formation of an extended π-conjugated ligand upon suitable electromagnetic radiation. Insights into the electronic structures of the complexes and the nature of their excited states have been obtained by DFT and TD-DFT calculations. These novel Pt(II) complexes were nanoorganized in polymer films which were poled, affording new materials characterized by a good second-order NLO response that can be easily switched, with an excellent NLO contrast. To the best of our knowledge, our compounds allowed designing the very first examples of switchable NLO polymer films based on metal complexes.
authors.affiliation: UMR 6226 CNRS-Université de Rennes 1, Institut des Sciences Chimiques de Rennes , Campus de Beaulieu, 35042 Rennes, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Boixel
authors.forename: Véronique
authors.initials: V
authors.lastname: Guerchais
authors.forename: Hubert
authors.initials: H
authors.lastname: Le Bozec
authors.forename: Denis
authors.initials: D
authors.lastname: Jacquemin
authors.forename: Anissa
authors.initials: A
authors.lastname: Amar
authors.forename: Abdou
authors.initials: A
authors.lastname: Boucekkine
authors.forename: Alessia
authors.initials: A
authors.lastname: Colombo
authors.forename: Claudia
authors.initials: C
authors.lastname: Dragonetti
authors.forename: Daniele
authors.initials: D
authors.lastname: Marinotto
authors.forename: Dominique
authors.initials: D
authors.lastname: Roberto
authors.forename: Stefania
authors.initials: S
authors.lastname: Righetto
authors.forename: Roberta
authors.initials: R
authors.lastname: De Angelis