Site-Isolated Electro-optic Chromophores Based on Substituted 2,2′-Bis(3,4-propylenedioxythiophene) π-Conjugated Bridges

Abstract

Application of bis(propylenedioxythiophene) (bis(ProDOT)) π-conjugated bridges bearing alkyl or aryl substituents in electro-optic (EO) chromophores is presented. A series of three bis(ProDOT)-based chromophores and a bithiophene-based control chromophore were prepared and fully characterized with regard to EO applications. The highly planar bis(ProDOT) bridge results in slightly larger (∼10%) molecular hyperpolarizability ( ) values as compared to the bithiophene bridge, as measured by hyperRayleigh scattering at a variety of wavelengths. In amorphous polycarbonate guest-host films, however, the bulky substituents on the bis(ProDOT) bridge result in significantly larger (∼70%) poling-induced EO coefficient (r 33 ) values, as measured by simple reflection ellipsometry at 1310 nm. This can be attributed to a roughly 2-fold enhancement in poling efficiency due to reduced intermolecular dipole-dipole interactions. This chromophore architecture also exhibits excellent temporal alignment stability and photochemical stability as compared to benchmark AJL8, FTC, and CLD chromophore systems. Incorporation of the strong CF 3 -phenyl-substituted tricyano-furan (TCF) acceptor into a bis(ProDOT)-based chromophore resulted in a zzz (-2ω;ω,ω) value at 1907 nm of 5700 ( 400 × 10 -30 esu and an r 33 value of 69 ( 14 pm/V at 32.8 total chromophore weight %.

Syntheses, Optical Properties, and Theoretical Investigation of Silafluorenes and Spirobisilafluorenes Bearing Electron‐Donating Aminostyryl Arms around a Silafluorene Core

“…Elemental analyses were performed by the Microanalytical Laboratory of Department of Chemistry, Faculty of Science, the University of Tokyo. 2,2'-Dibromo-5,5'-diiodobiphenyl (5), [13] diethyl 4-(diethylamino)benzylphosphonate (7), [19] diethyl 4-(di-n-hexylamino)benzylphosphonate (11), [20] and 2,2'-dibromo-4,4'-diiodobiphenyl (9) [21] were prepared according to literature procedures.…”

Using phenoxazine and phenothiazine as electron donors for second-order nonlinear optical chromophore: Enhanced electro-optic activity

“…After removal of the solvent under reduced pressure, the crude product was purified by silica chromatography, eluting with (AcOEt: Hexane ¼ 1:5) to give chromophore L1 as a green solid in 65.3% yield (0. 19 The procedure for chromophore L1 was followed to prepare chromophore L2 from 5b as a green solid in 63.2% yield (0. 19 …”

“…19 The procedure for chromophore L1 was followed to prepare chromophore L2 from 5b as a green solid in 63.2% yield (0. 19 …”

Nano-Engineering of Molecular Interactions in Organic Electro-Optic Materials

“…This method of "site (chromophore)-isolation" has been shown to limit chromophore aggregation (Liao et. al., 2005;Hammond et. al., 2008;.…”