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We have developed three nonlinear optical chromophores A-C with the same diethylaminophenyl donor and tricyanovinyldihydrofuran acceptor coupled through isophorone bridge. The donor and bridge moiety of chromophores B and C are modified with functional group pentafluorobenzene and alkylaniline cyanoacetate (C1), respectively. In particular, the alkylaniline cyanoacetate group is not only a steric group, but also a short chromophore. Except for the steric effect, two C1 groups with considerable dipole moment will greatly weaken the electrostatic interaction between molecules by electrostatic screening effect before poling thus increasing the poling efficiency. Electro-optical films doped with chromophore A-C have been poled to give quite different r 33 values of 69, 115 and 166 p.m./V at 1.31 μm, respectively. The normalized r 33 value of chromphore C was up to 8.16 × 10−19 p.m. cc per (V molecules) which is more than four times higher than that of chromophore A without functional group. Image 1 • Three chromophores A-C with different isolation groups had been synthesized. • The r 33 value of film-A/PMMA and C/PMMA is 69 and 166 p.m./V, respectively, at 1.31 μm. • The decomposition temperatures of chromophore C are higher than 270 °C. [ABSTRACT FROM AUTHOR]