Abstract
We studied the effect of a cross-conjugated bridging group (χC) on charge-transfer in a push-pull chromophore system. The hyperpolarizability of such molecules was found to be comparable to that of a fully π-conjugated molecule (πC) with the same donor and acceptor. The cross-conjugated moiety was then applied as a pendant to a fully π-conjugated chromophore containing a tricyanopyrroline acceptor (TCP). The addition of a χC moiety did not alter the intrinsic hyperpolarizability and provides an avenue for extending and aiding πC systems. The molecules were examined by X-ray diffraction (XRD), hyper-Raleigh scattering (HRS) and UV-visible (UV-vis) spectroscopy. Experimental results were compared with the predictions of density functional theory (DFT). Cross-conjugated molecules have comparable ß values, relative to πC molecules, due to reduced spatial overlap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). Thus, the χC architecture could facilitate independent modification of donor and acceptor strengths while minimizing unfavorable effects on electronic transitions and dipole moments.
Similar content being viewed by others
References
M.H. van der Veen, {etet al.}, Adv. Funct. Mater. 14, 215 (2004).
A. Almenningen {etet al.}, Acta Chem. Scand. 42A, 634 (1988).
T.M. Swager and R.H. Grubbs, J. Am. Chem. Soc. 109, 894 (1987).
P.L. Wu {etet al.}, Chem. Commun. 5421 (2009).
X.J. Feng {etet al.}, Chem.–Eur. J. 17, 2518 (2011).
T. Michinobu {etet al.}, Chem. Commun. 737 (2005).
J.C. May {etet al.}, Opt. Lett. 30, 3057 (2005).
T. Michinobu {etet al.}, Chem.–Eur. J. 12, 1889 (2006).
R.R. Tykwinski and Y. Zhao, Synlett 1939 (2002).
Y. Zhao and R.R. Tykwinski, J. Am. Chem. Soc. 121, 458 (1999).
C.A. van Walree, {etet al.}, Eur. J. Org. Chem. 2004, 3046 (2004).
G.C. Solomon {etet al.}, J. Am. Chem. Soc. 130, 7788 (2008).
T. Kodaira {etet al.}, J. Chem. Soc. Faraday Trans. 93, 3039 (1997).
P. Kaatz and D.P. Shelton, J. Chem. Phys. 105, 3918 (1996).
J.L. Oudar and D.S. Chemla, J. Chem. Phys. 66, 2664 (1977).
S.J. Benight {etet al.}, J. Phys. Chem. B 114, 11949 (2010).
A.F. Tillack {etet al.}, in Mater. Res. Soc. Symp. Proc. (this issue).
M.J. Cho {etet al.} Dyes Pigments 79, 193 (2008).
D.H. Bale, Ph.D. Thesis, University of Washington, 2008.
Acknowledgments
This material is based upon work supported by the National Science Foundation under Grant Numbers DMR-0905686, DMR-0120967, DMR-1303080 and PREM DMR-0934212. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. The authors also acknowledge partial financial support from the Air Force Office of Scientific Research (FA9550-09-1-0589 and FA9550-09-1-0682).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Rawal, M., Garrett, K., Tillack, A.F. et al. Cross-conjugation as a Motif for Organic Non-Linear Optical Molecules. MRS Online Proceedings Library 1698, 14–19 (2014). https://doi.org/10.1557/opl.2014.793
Published:
Issue Date:
DOI: https://doi.org/10.1557/opl.2014.793