Third-order nonlinear optical properties and structures of (E)-N-(4-nitrobenzylidene)-2,6-dimethylaniline and (E)-N-(4-nitrobenzylidene)-2,3-dimethylaniline

Growth and characterization of organic material 4-dimethylaminobenzaldehyde single crystal

The organic material 4-dimethylaminobenzaldehyde single crystals were grown by slow evaporation technique. The grown crystal was confirmed by the single crystal and powder X-ray diffraction analyses. The functional groups of the crystal have been identified from the Fourier Transform Infrared (FTIR) and FT-Raman studies. The optical property of the grown crystal was analyzed by UV-Vis-NIR and photoluminescence (PL) spectral measurements. The thermal behavior of the grown crystal was analyzed by thermogravimetric (TG) and differential thermal analyses (DTA). Dielectric measurements were carried out with different frequencies by using parallel plate capacitor method. The third order nonlinear optical properties of 4-dimethylaminobenzaldehyde was measured by the Z-scan technique using 532 nm diode pumped continuous wave (CW) Nd:YAG laser.

Crystal growth and characterization of an organic nonlinear optical single crystal: 2,3-Dimethyl-N-[4-(Nitro) benzylidene] aniline

An organic nonlinear optical material 2,3-Dimethyl-N-[4-(Nitro) benzylidene] aniline was synthesized by condensation reaction. The single crystals were grown by the slow evaporation technique at room temperature using ethyl acetate as solvent with large in size and having transparent nature. The unit cell parameters were determined and belong to a noncentrosymmetric orthorhombic crystal structure by single crystal X-ray diffraction. The crystalline nature of the synthesized material was recorded by the powder X-ray diffraction pattern. The molecular structure of the grown material was investigated by proton and carbon nuclear magnetic resonance, mass spectrum analysis. Functional groups were identified by the vibration spectrum analysis. The optical absorbance of the grown crystal was ascertained by Ultraviolet-Visible spectrum. Thermal behaviour and stability of the grown material was investigated by thermo gravimetric/differential thermal analysis. The nonlinear optic conversion efficiency was determined by powder technique and found to be 4.08 times greater that of KDP as a standard reference.

Structural, proton-transfer, thermodynamic and nonlinear optical studies of (E)-2-((2-hydroxyphenyl)iminiomethyl)phenolate

Recently, the study of imine-bridged organics is interested in proton-transfer and photo-responsive material fields. Herein, we make a investigation on the structural, thermodynamic and nonlinear optical properties of (E)-2-((2-hydroxyphenyl)iminiomethyl)phenolate (HPIMP). The structural varieties of the studied compound are characterized by the X-ray single crystal diffraction and vibrational spectral techniques, as well as the vibrational spectral bands are precisely ascribed to the studied structure with the aid of DFT theoretical calculations. The experimental results of the FT-IR and X-ray measurements supply good proofs to reveal the proton-transfer procedures of HPIMP, and exhibit that the studied compound is a good proton-transfer model. In addition, the thermodynamic properties are obtained from the theoretical vibrations of the optimized HPIMP. The linear polarizability (α(0)) and first-order hyperpolarizabilities (β(0)) respectively present the values of 26.28 Å(3) and 7.41×10(-30) cm(5)/esu predicated theoretically by the DFT-B3lYP method at 6-31G(d) level, which indicates that the studied compound is a promising nonlinear optical material candidate.

Synthesis, vibrational spectral and nonlinear optical studies of N-(4-hydroxy-phenyl)-2-hydroxybenzaldehyde-imine: a combined experimental and theoretical investigation

The study of imine-bridged organics has been the one hot spot of photo-responsive material sciences in recent years. Herein we make a study of the synthesis, characteristics and potential application of N-(4-hydroxy-phenyl)-2-hydroxy-benzaldehyde-imine (HPHBI), C13H11NO2. The studied compound was synthesized in one step by the condensation reaction of salicylaldehyde and 4-aminophenol in methanol solution, and characterized by single crystal X-ray diffraction, FT-IR and FT-Raman techniques with theoretical calculations at B3LYP/6-31G(d) level. The molecule adopts trans configuration about central CN bond with intramolecular hydrogen bonding, and the adjacent molecules form wave-shaped structure linked by strong intermolecular hydrogen bonding mechanism along b axis. The vibrational spectra have been precisely assigned with the aid of theoretical frequencies. Furthermore, the thermodynamic properties have been obtained by the theoretical vibrational analysis for HPHBI. The total linear polarizability and first-order hyperpolarizabilities calculated on the studied compound respectively present 25.378 Å3 and 1.655×10(-29) cm5/esu, which indicates the compound has relatively good nonlinear optical property.