Design and photoinduced surface relief grating formation of photoresponsive azobenzene based molecular materials with ruthenium acetylides

Abstract

International audienceNovel photoresponsive materials based on ruthenium(II) σ-acetylides coupled to an azobenzene moiety in the main π-conjugated chain have been synthesized. The introduction of a metal acetylide fragment in the same conjugated chain as the azobenzene induces the trans-cis-trans isomerization of the azo unit, while the rate of the thermal cis → trans back isomerization increases with increasing overall electron richness of these compounds. These azobenzene-containing ruthenium(II) acetylides show satisfactory processability and give rise to spin-coated uniform thin films. Formation of surface-relief gratings on their amorphous thin films and in a PMMA polymer matrix using a picosecond pulsed laser at 532 nm results in instantaneous inscription: saturation of the first order diffraction efficiency and of the modulation amplitude of gratings were obtained in less than 1 s, while the orientation of these azodyes remains unchanged for up to 6 months

Effect of metal complexation on the nonlinear optical response of a conjugated ligand

“…The former can be attributed to the pyridine and phenyl intraligand transitions, while the latter can be attributed to a combination of metal-to-ligand (in the case of the metallic complex) and intraligand charge transfers [15][16][17][18][19][20].…”

Nonlinear optical properties of intriguing Ru σ-acetylide complexes and the use of a photocrosslinked polymer as a springboard to obtain SHG active thin films

“…The azo-containing bifunctional rutheniumacetylides 1 and 2 were then prepared according to previously published experimental procedures, as shown in Scheme 2. 11 Complex 1 15 The completion of the reaction was monitored by 31 P NMR. After removing the excess of 4-ethynylbenzaldehyde, addition of 4b, and subsequent deprotonation by triethylamine in the presence of KPF 6 , afforded complex 2 as a red powder in 52% yield from [(dppe) 2 RuCl(OTf)].…”

Photoisomerisation in Aminoazobenzene‐Substituted Ruthenium(II) Tris(bipyridine) Complexes: Influence of the Conjugation Pathway

“…Ligand L3 is similar to L2 except that the linker contains a triazole moiety. The effect of the ligand types on the photophysical properties (absorption, emission and photoisomerisation) of the ligands ( L1 – L3 ) and complexes Ru L1 – L3 are investigated experimentally and theoretically, and compared with the simple models L4 11 (Scheme ) and [Ru(bpy) 3 ](PF 6 ) 2 .…”

“…L1 and L2 exhibit ad onor-conjugated bridge-acceptor (D-p-A) structure, but differ in the position, nature and length of the conjugated bridge. Whereas for L1 the azo unit is directly linked to the 4-position of the bipyridine, it is linked to the bipyridine by an ethynyl bridge at the 5-positioni nL2.L igand L3 is similart oL2 except that the linker contains at riazole moiety.T he effect of the ligand types on the photophysical properties (absorption, emission and photoisomerisation)o ft he ligands( L1-L3)a nd complexes Ru L1-L3 are investigated experimentally and theoretically,a nd compared with the simple models L4 [11] (Scheme 1) and [Ru(bpy) 3 ](PF 6 ) 2 .…”