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Second-order Nonlinear Optical Properties (second-order + nonlinear_optical_property)
Selected AbstractsSynthesis, Crystal Structure, and Second-Order Nonlinear Optical Properties of Ruthenium(II) Complexes with Substituted Bipyridine and Phenylpyridine LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2006Laurence Labat Abstract Two new ruthenium(II) complexes of formula [Ru(bpy)2(L1)][PF6] and [Ru(bpy)2(L2)][PF6]2 are reported. HL1 is a (nitrophenyl)ethenyl-substituted phenylpyridine ligand, and L2 is the bipyridine analogue of HL1. The X-ray crystal structure of [Ru(bpy)2(L1)][PF6] has been solved, and the compound is found to crystallize in the monoclinic C2/c space group. The electronic spectrum of the cyclometalated derivative [Ru(bpy)2(L1)][PF6] exhibits a low-lying transition that is red-shifted from 454 to 546 nm relative to that of the parent bipyridine-based complex, which reveals an important charge-transfer character. To support this assumption, the nonlinear optical properties were investigated by the hyper-Rayleigh scattering technique and indicate a molecular static hyperpolarizability (,0) equal to 230,×,10,30 cm5,esu,1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Second-Order Nonlinear Optical Properties of Tetraaza-Coordinated Nickel(II) ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2003Santo Di Bella Abstract In this contribution, we report the design and theoretical analysis, using the INDO/SCI-SOS quantum chemical formalism, of novel molecular architectures based on planar [N4]-, (2-aminobenzylideneiminato)- and tetraazamacrocycle-coordinated nickel(II) complexes, having second-order nonlinear optical (NLO) properties. Calculations indicate that these molecules possess comparable, or even larger, second-order nonlinearity to the bis(salicylaldiminato)NiII Schiff-base analogues. The nonlinearity of substituted complexes is dominated by the nature and position of substituents on the tribenzo[b,f,l] and/or cyclotetradecine rings, and is determined by the relative directions of the ground- and excited-state dipole moments. Moreover, substitution with acceptor groups in the dibenzo[b,l] rings involves a significant octupolar contribution to optical nonlinearity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Observing Second-Order Nonlinear Optical Properties by Symmetry Breaking in Centrosymmetric Furan-Containing Oligoaryl CyclophandienesCHEMISTRY - A EUROPEAN JOURNAL, Issue 47 2009Hsin-Chieh Lin Dr. Abstract Centrosymmetric furan-containing cyclophandienes 3 and 4, synthesized by our furan annulation protocol, have been shown to exhibit extraordinarily large Stokes shifts and second-order nonlinear optical , values. The , values for 3 and 4 measured at 1.32,,m are 208 and 530×10,30,esu, respectively. The , values of 3 and 4 are similar to those of respective cyclophenes 1,a and 7 in which strong hyperpoarizable interactions between two twisted ,-systems (oligoaryl and bridging double bond) might take place. Symmetry breaking due to the resonance contribution (cf. 2) and the unique structural features of 3 and 4 has been used to account for this unusual photophysical behavior. [source] Theoretical Study on Second-order Nonlinear Optical Properties of Substituted Thiazole DerivativesCHINESE JOURNAL OF CHEMISTRY, Issue 4 2001Yong-Jun Liu Abstract On the basis of ZINDO program, we have designed a program to calculate the nonlinear second-order polarizability ,yk and ,, according to the SOS expression. The second-order nonlinear optical properties of 4-nitro-4,-dimethylamino-stilbene and a series of its thiazole derivatives were studied. The calculated results were that: When replacing a benzene ring in 4-nitro-4,-dimethylamino-stilbene by a thiazole ring, the influence on , values depends on the position of thiazole ring. When the thiazole ring connects with nitro group (acceptor), the , values increase significantly compared with corresponding stilbene derivatives. The , values of 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are larger than those of 2-(p -nitro-,-styryl)-5-donor-thiazole derivatives (8,13) and 2-(p -donor-phenyl)-azo-5-nitro-thiazole derivatives (14,19). The 2-(p -donor-,-styryl)-5-nitro-thiazole derivatives (2,7) are good candidates as chromophores duo to their high nonlinearities and potential good thermal stability. [source] New Organic Nonlinear Optical Polyene Crystals and Their Unusual Phase Transitions,ADVANCED FUNCTIONAL MATERIALS, Issue 11 2007O-P. Kwon Abstract A series of new nonlinear optical chromophores based on configurationally locked polyenes (CLPs) with chiral pyrrolidine donors are synthesized. All CLP derivatives exhibit high thermal stability with decomposition temperatures Td at least > ,270,°C. Acentric single crystals of enantiopure D - and L -prolinol-based chromophores with a monoclinic space group P21 exhibit a macroscopic second-order nonlinearity that is twice as large than that of analogous dimethylamino-based crystal. This is attributed to a strong hydrogen-bonded polar polymer-like chain built by these molecules, which is aligned along the polar crystallographic b -axis. Five ,-phase CLP crystals with different donors grown from solution exhibit a reversible or irreversible thermally induced structural phase transition to a ,-phase. These phase transitions are unusual, changing the crystal symmetry from higher to lower at increasing temperatures, for example, from centrosymmetric to non-centrosymmetric, enhancing their macroscopic second-order nonlinear optical properties. [source] Theoretical study on the second-order nonlinear optical properties of nonconjugated D-,-A chromophoresINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 7 2009Guochun Yang Abstract Density functional theory calculations have been carried out on nonconjugated D-,-A chromophores to investigate the different electron donors and conjugated bridges effects on the molecular nonlinear optical response. The results show that the large second-order polarizability values can be achieved through careful combination of available electron donors, conjugated bridges for our studied nonconjugated D-,-A chromophores. The calculations also provide a clear explanation for the second-order polarizability changes from the standpoint of transition energies, oscillator strengths, electron density difference, and bond length alternation. Solvent effect has great influence on the second-order polarizability and electronic absorption spectrum. It is hoped that the results presented in this article will give some hints to the interrelated studies. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] Synthesis and second-order nonlinear optical properties of multifunctional polysiloxanes with sulfonyl-based chromophoresJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2005Jianli Hua Abstract Two new polysiloxanes (P1 and P2) with a high density of sulfonyl-based chromophores were prepared by a new two-step method. Poly[methyl-3-(9-carbazolyl)propyl siloxane] was partially formulated by the standard Vilsmeier reaction, and formyl groups of high reactivity were condensed with cyanoacetylated chromophores; this yielded polysiloxanes P1 and P2 in almost complete conversions. Their structures were verified with 1H NMR, IR, and ultraviolet,visible spectra. P1 and P2 exhibited good solubility in common organic solvents and were thermally stable. The maximum absorptions appeared at about 452 and 390 nm for P1 and P2, respectively, in tetrahydrofuran; they were blueshifted about 42 and 8 nm, respectively, in comparison with those of the corresponding chromophores with a nitro acceptor and resulted in a wider transparency window. The P1 values of the nonlinear optical coefficient (d33), measured by in situ second harmonic generation, was 16.2 pm/V. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1317,1324, 2005 [source] Functional [6]Pericyclynes: Aromatization to Substituted carbo -Benzenes,CHEMISTRY - A EUROPEAN JOURNAL, Issue 17 2007Catherine Saccavini Dr. Abstract Reductive treatment of stereoisomeric mixtures of variously substituted hexaoxy[6]pericyclynes with SnCl2/HCl led to the corresponding substituted carbo -benzenes. Tetramethoxyhexaphenyl[6]pericylynediol and dimethoxyhexaphenyl[6]pericyclynetetrol thus proved to be alternative precursors of hexaphenyl- carbo -benzene, previously described. Another hexaaryl- carbo -benzenic chromophore with 4-pyridyl and 4-anisyl substituents was targeted for its second-order nonlinear optical properties and was obtained by aromatization of a dimethoxy[6]pericyclynetetrol. Two alkynyl substituents in para positions were also found to be compatible with the C18carbo -benzene ring, provided that the four remaining vertices are substituted by phenyl groups. In the protected series, bis(trimethylsilylethynyl)hexaphenyl- carbo -benzene (C18Ph4(CCTMS)2) could be isolated and fully characterized, even by X-ray crystallography. In the bis-terminal series, the diethynylhexaphenyl- carbo -benzene C18Ph4(CCH)2 could not be isolated in the pure form. It could, however, be generated by two different methods and identified by the corresponding 1H NMR spectra. Unsubstituted carbo -benzene C18H6 remains unknown, but tetraphenyl- carbo -benzenes C18Ph4H2 with two unsubstituted vertices proved to be viable molecules. Whereas the "para" isomer could be characterized by MS and 1H and 13C NMR spectroscopy only in a mixture with polymeric materials, the "ortho" isomer (with adjacent CH vertices) could be isolated, and its structure was determined by using X-ray crystallography. The structure calculated at the B3PW91/6-31G** level of theory turned out to be in excellent agreement with the experimental structure. The 1H and 13C NMR chemical shifts of hexa- and tetraphenyl- carbo -benzenes were also calculated at the B3LYP/6-31+G** level of theory and were found to correlate with experimental spectra. The remote NMR deshielding of peripheral protons (through up to five bonds) revealed a very strong diatropic circulation around the C18 ring, regardless of the substitution pattern. In full agreement with theoretical investigations, it has been demonstrated experimentally that the carbo -benzene ring is "independently" aromatic, in accord with structural,energetic and ,magnetic criteria. [source] | |||||||||||||