Hypeipolarizability

The term in parentheses vanishes for any molecule thatpossesses reflection planes, a center of inversion, or rotation-reflection axes, and jS is thus only non-zero for a chiral molecule. It is of opposite sign for the enantiomers of a chiral molecule. In Rayleigh-Schrodinger perturbation theory the isotropic component of the first electric-dipolar hypeipolarizability at Wj = Wj q- may be written as... 

In the case of molecules having inversion symmetry, as non-substituted phthalocyanines, all the components of the first hypeipolarizability p are zero. For this reason, appropriately substituted phthalocyanines have to be designed if one wishes to obtain efficient second-order NLO responses. Thus, theoretical calculations developed at the end of the 80 s by T. J. Marks and coworkers [29] suggested that push-pull unsymmetrically substituted phthalocyanines with suitable electron-donor and acceptor groups and efficient intramolecular charge transfer should yield interesting compounds for second-order applications. 

Vance, F.W., Karki, L., Reigle, J.K., Hupp, J.T., Ratner, M.A. Aspects of intervalence charge transfer in cyanide-bridged systems modulated electric field assessment of distances, polarizability changes, and anticipated first hypeipolarizability characteristics. J. Phys. Chem. A 102, 8320-8324 (1998)... 

Figure 3. Dispersion of the nonlinear optical susceptibility djs of DCANP. The curve is a theoretical fit using a two-level model for the nonlinear optical hypeipolarizability of the DCANP molecules.

Ashwell, et al., have shown that small molecules with large molecular hypeipolarizabilities can be used to build up relatively thick NLO films which have large second harmonic coefficients ( ). Penner, et al, demonstrated that 0.5-micron thick NLO films of high optical quality could be fabricated by LBK heterolayer deposition of side chain polymers (9). Recentiy, Lindsay, et al., reported the use of two mainchain chromophoric polymers to fabricate LBK heterolayer NLO films (10). 

B. Kirtman and M. Hasan, Chem. Phys. Lett., 57, 123 (1989). Ab Initio Longitudinal Polarizabilities and Hypeipolarizabilities for Polydiacetylene and Polybutatriene Oligomers. For the long-chain semiempirical calculations, see B. Kirtman, Int.. Quantum Chem., to be published. Finite Chain Approximation for Linear and Non-Linear Polarizabilities of Polydiacetylene and Polybutatriene. 

Figure 4. The dipole moment (aX polarizability anisotropy Aa Q>), first hypeipolarizability P (cX and figure of merit FOM (d), as a fimction of bond order alternation fi>r the molecule (CI%)2 N(CHK304 (see (27 and...

G. Maroulis, Accurate electric multipole moment, static polarizability and hypeipolariz-ability derivatives for N2. J. Chem. Phys. 118(6), 2673-2687 (2003)... 

X. Li, K.L.C. Hunt, J. Pipin, D.M. Bishop, Long-range, collision-induced hypeipolariz-abilities of atoms or centrosymmetric linear molecules theory and numcaical results for pairs containing H or He. J. Chem. Phys. 105(24), 10954-10968 (1996)... 

T. Bancewicz, G. Maroulis, Rotationally adapted studies of ab initio-computed collision-induced hypeipolarizabilities the H2-Ar pair. Phys. Rev. A 79(4), 042704 (2009)... 

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