Donor-acceptor chromophore

The majority of molecules with the required properties are donor-acceptor chromophores which fall into the following structural pattern electron-donor-(-electron-bridge-electron-acceptor, typical of many classical absorbing dyes (Chapter 2). 

Second order optical nonlinearity can be induced in polymeric systems containing dipolar (donor-acceptor) chromophores. The chromophore can be a molecular species attached to the host chain or it can be incorporated in the polymeric structure itself. In general, a good chromophore has an electron donating group connected to an electron... 

Many colored molecules can be described as donor-acceptor chromophores. In such cases, the longest-wavelength absorption depends on the extension of the conjugated system and on the amount of bond length equalization which is... 

Donor-acceptor chromophores, 134. 218 Donor-acceptor complex, 281. 465... 

This three-step assembly method is suitable for a wide range of donor-acceptor chromophore precursors, such as stilbazole, acetylenic, azobenzene [131,132], or pyrrole [133] resulting in films with very large NLO/EO responses ( /a> of 150-220 pm/V and r33 values as high as —80 pm/V). 

Platinum bis(alkynyl) species have been used as Tt-bridging groups in donor-acceptor chromophores, some... 

Mercury has also been inserted into the bridge of donor-acceptor chromophores and affords increased transparency relative to comparable all-organic bridges thus, a /3-value of 26 X 10 esu has been reported for 195 (Figure 16), compared to values of 24 and 28 x 10 esu for corresponding tolane (compound 195 minus the Hg) and bis(phenyl)-butadiyne analogs, respectively, while the absorption maxima are 307 nm for 195 and 379-384 nm for the all-organic... 

Facchetti, A. Abbotto. A. Beverina, L. van der Boom, M.E. Dutta, P. Evmenenko. G. Pagani. G.A. Marks, T.J. Layer-by-layer self-assembled pyrrole-based donor-acceptor chromophores as electro-optic materials. Chem. Mater. 2003. 15 (5), 1064. 

Wong, M. S., Bosshard, C., Pan, F., and Gunter, P., Non-classical donor-acceptor chromophores for second order nonlinear optics, Adv. Mater., 8, 677-680 (1996). 

Fig. 5. Tsrpical linear donor-acceptor chromophore (DANS) (a) ground state and (b) first excited state structures.

Figure 9.10 Longest-wavelength absorption maxima of donor-acceptor chromophores.

Takagi, K., Ozaki, M., Nakatsu, K., Matsuoka, M., and Kitao, T., Nonlinear optical properties and structure of biphenyl containing donor-acceptor chromophores and bulky substituents, Chem. Lett., 173, 1989. 

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