Molecular Design of Synthetic Polypeptides for Nonlinear Optics

Abstract : Second order molecular susceptibilities B of Poly (y benzyl L-glutamate)(PBLG) and poly(y -p-nitrobenzyl Lglutamate) (PNBLG) were determined by means of dc-induced second harmonic generation (dc-SHG) technique in solutions at a wavelength of 1064nm as 1.5x10-29 esu and -4.9xlO-29 esu, respectively. Among PBLG, PNBLG and nitrobenzene, it was found that only PNBLG has negative value of B. It follows that the effect of nitrophenyl groups in side chains is dominant for B whereas the contribution of carbonyl groups in main chain is dominant for the permanent dipole moment u in PNBLG.

[1]  Kenneth D. Singer,et al.  Second harmonic generation in poled polymer films , 1986 .

[2]  B. F. Levine,et al.  Second order hyperpolarizability of a polypeptide α‐helix: Poly‐γ‐benzyl‐L glutamate , 1976 .

[3]  D. A. Kleinman,et al.  Nonlinear Dielectric Polarization in Optical Media , 1962 .

[4]  G. Boyd,et al.  Linear and nonlinear optical properties of AgGaS 2 , CuGaS 2 , and CuInS 2 , and theory of the wedge technique for the measurement of nonlinear coefficients , 1971 .

[5]  Kenneth D. Singer,et al.  Measurements of molecular second order optical susceptibilities using dc induced second harmonic generation , 1981 .

[6]  A. Wada,et al.  Electrooptical and dielectric investigations on the conformation and the electrical properties of poly‐γ‐benzyl‐L‐glutamate in mixed solvents , 1964 .

[7]  P. Doty,et al.  Polypeptides. IV. The Molecular Weight, Configuration and Association of Poly-γ-benzyl-L-glutamate in Various Solvents , 1956 .

[8]  David J. Williams,et al.  Optical and nonlinear optical characterization of molecularly doped thermotropic liquid crystalline polymers , 1982 .

[9]  David J. Williams,et al.  Characterization of Liquid Crystalline Polymers for Electro-optic Applications , 1983 .

[10]  A. F. Garito,et al.  Dispersion of the nonlinear second-order optical susceptibility of organic systems (A) , 1983 .

[11]  B. F. Levine,et al.  Second and third order hyperpolarizabilities of organic molecules , 1975 .

[12]  Kenneth D. Singer,et al.  Exceptional second‐order nonlinear optical susceptibilities of quinoid systems , 1981 .

[13]  J. Oudar,et al.  Hyperpolarizabilities of the nitroanilines and their relations to the excited state dipole moment , 1977 .

[14]  R. W. Terhune,et al.  Effects of Dispersion and Focusing on the Production of Optical Harmonics , 1962 .

[15]  C. Bethea.  Experimental technique of dc induced SHG in liquids: measurement of the nonlinearity of CH(2)I(2). , 1975, Applied optics.