Linear an d nonlinear optical propertie s of stilba zolium de rivatives

Molec ular organic materials having nonlinear opti cal (NLO) properties are required for applications in e merging opt oelectronic and photonic technologies. NLO ar e useful because they allow the m anipulation of laser beams, e.g., in frequency d oubling or second har monic gener ation (SHG), a quadrati c effect. Am ong known NLO comp ounds, stilbazolium salts are partic ularly attractive for use in devices. Stilbazoliu m chromoph ores have b een incorpo rated into various macroscopic structures such as Langmuir-Blodgett (LB) films, intercalated layer materials, self-as sembled sup erlattices, inclusion co mplexes an d guest-ho st and side-chain polymer films. With the sole exception o f a theoretical study on the N-alkyl stilbazolium salts only N -aryl stilba zolium salts have been p reviously studied for their NLO properties.[۱] The present stud y is dedicatedto perform a theore tical investigation about the linear and nonlin ear optic al (NLO) properties, represented as, dipole polarizability Į, firsthy perpolarizability ȕ and secondhyperpolarizability Ȗ, respectively, trans-۴ǯ-(R)-N- methyl-۴-stilbazolium (R = Brome Br, methyl Me , Amino NH۲, Dimethylamino N Me۲, Hydroxy OH, M ethoxy MeO ). With this aim, we make a co mparative study between the prope rties of thes e molecules to rationaliz e the differ ences in their properties in terms of the R group into the ۱-m ethyl-۴-sty ryl-pyridiniu m.

کلیدواژه ها:

Nonlinear optical properties ، stilbazolium ، Hartree-Fock ، DFT.