Rational Enhancement of Second-Order Nonlinearity: Bis-(4-methoxyphenyl)hetero-aryl-amino Donor-Based Chromophores: Design, Synthesis, and Electrooptic Activity

@article{citeulike:3044450, abstract = {Abstract: Two new highly hyperpolarizable chromophores, based on N,N-bis-(4-methoxyphenyl)aryl-amino donors and phenyl-trifluoromethyl-tricyanofuran (CF3-Ph-TCF) acceptor linked together via \`{A}-conjugation through 2,5-divinylenethienyl moieties as the bridge, have been designed and synthesized successfully for the first time. The aryl moieties on the donor side of the chromophore molecules were varied as to be thiophene and 1-n-hexylpyrrole. The linear and nonlinear optical (NLO) properties of all compounds were evaluated in addition to recording relevant thermal and electrochemical data. The properties of the two new molecules were comparatively studied. These results are critically analyzed along with two other compounds, reported earlier from our laboratories and our collaborators, that contain (i) aliphatic chain-bearing aniline and (ii) dianisylaniline as donors, keeping the bridge (2,5-divinylenethienyl-), and the acceptor (CF3-Ph-TCF), constant. Trends in theoretically (density functional theory, DFT) predicted, zero-frequency gas-phase hyperpolarizability [²(0;0,0)] values are shown to be consistent with the trends in ²HRS(2\'{E};\'{E},\'{E}), as measured by Hyper-Rayleigh Scattering (HRS), when corrected to zero-frequency using the two-level model (TLM) approximation. Similarly, trends in poling efficiency data (r33/Ep) and wavelength dispersion measured by reflection ellipsometry (using a TengMan apparatus) and attenuated total reflection (ATR) are found to fit the TLM and DFT predictions. A 3-fold enhancement in bulk nonlinearity (r33) is realized as the donor subunits are changed from alkylaniline to dianisylaminopyrrole donors. The results of these studies provide insight into the complicated effects on molecular hyperpolarizability of substituting heteroaromatic subunits into the donor group structures. These studies also demonstrate that, when frequency dependence and electric-field-induced ordering behavior are correctly accounted for, ab initio DFT generated ²(0;0,0) is effective as a predictor of changes in r33 behavior based on chromophore structure modification. Thus DFT can provide valuable insight into the electronic structure origin of complex optical phenomena in organic media.}, address = {Department of Chemistry, University of Washington, 109 Bagley Hall, Box 351700, Seattle, Washington 98195}, author = {Davies, Joshua A. and Elangovan, Arumugasamy and Sullivan, Philip A. and Olbricht, Benjamin C. and Bale, Denise H. and Ewy, Todd R. and Isborn, Christine M. and Eichinger, Bruce E. and Robinson, Bruce H. and Reid, Philip J. and Li, Xiaosong and Dalton, Larry R. }, citeulike-article-id = {3044450}, doi = {10.1021/ja8007424}, journal = {J. Am. Chem. Soc.}, keywords = {dcdhf}, month = {July}, posted-at = {2008-07-26 07:02:11}, priority = {2}, title = {Rational Enhancement of Second-Order Nonlinearity: Bis-(4-methoxyphenyl)hetero-aryl-amino Donor-Based Chromophores: Design, Synthesis, and Electrooptic Activity}, url = {http://dx.doi.org/10.1021/ja8007424}, year = {2008} }

TY - JOUR ID - citeulike:3044450 L3 - citeulike-article-id:3044450 TI - Rational Enhancement of Second-Order Nonlinearity: Bis-(4-methoxyphenyl)hetero-aryl-amino Donor-Based Chromophores: Design, Synthesis, and Electrooptic Activity JF - J. Am. Chem. Soc. AD - Department of Chemistry, University of Washington, 109 Bagley Hall, Box 351700, Seattle, Washington 98195 N2 - Abstract: Two new highly hyperpolarizable chromophores, based on N,N-bis-(4-methoxyphenyl)aryl-amino donors and phenyl-trifluoromethyl-tricyanofuran (CF3-Ph-TCF) acceptor linked together via À-conjugation through 2,5-divinylenethienyl moieties as the bridge, have been designed and synthesized successfully for the first time. The aryl moieties on the donor side of the chromophore molecules were varied as to be thiophene and 1-n-hexylpyrrole. The linear and nonlinear optical (NLO) properties of all compounds were evaluated in addition to recording relevant thermal and electrochemical data. The properties of the two new molecules were comparatively studied. These results are critically analyzed along with two other compounds, reported earlier from our laboratories and our collaborators, that contain (i) aliphatic chain-bearing aniline and (ii) dianisylaniline as donors, keeping the bridge (2,5-divinylenethienyl-), and the acceptor (CF3-Ph-TCF), constant. Trends in theoretically (density functional theory, DFT) predicted, zero-frequency gas-phase hyperpolarizability [²(0;0,0)] values are shown to be consistent with the trends in ²HRS(2É;É,É), as measured by Hyper-Rayleigh Scattering (HRS), when corrected to zero-frequency using the two-level model (TLM) approximation. Similarly, trends in poling efficiency data (r33/Ep) and wavelength dispersion measured by reflection ellipsometry (using a TengMan apparatus) and attenuated total reflection (ATR) are found to fit the TLM and DFT predictions. A 3-fold enhancement in bulk nonlinearity (r33) is realized as the donor subunits are changed from alkylaniline to dianisylaminopyrrole donors. The results of these studies provide insight into the complicated effects on molecular hyperpolarizability of substituting heteroaromatic subunits into the donor group structures. These studies also demonstrate that, when frequency dependence and electric-field-induced ordering behavior are correctly accounted for, ab initio DFT generated ²(0;0,0) is effective as a predictor of changes in r33 behavior based on chromophore structure modification. Thus DFT can provide valuable insight into the electronic structure origin of complex optical phenomena in organic media. KW - dcdhf AU - Davies, Joshua AU - Elangovan, Arumugasamy AU - Sullivan, Philip AU - Olbricht, Benjamin AU - Bale, Denise AU - Ewy, Todd AU - Isborn, Christine AU - Eichinger, Bruce AU - Robinson, Bruce AU - Reid, Philip AU - Li, Xiaosong AU - Dalton, Larry PY - 2008/07/19/ UR - http://dx.doi.org/10.1021/ja8007424 ER -