K. Janardhana

Synthesis and Characterization of Organic NLO Compound

Organic compound 1‐(2 thiophene)‐3‐(2, 3, 5‐trichloroph enyl)‐2‐propen‐1‐one [TTCP] with molecular formula C13H7Cl3OS was synthesized using condensation reaction method. FT‐IR spectra were recorded to identify the various functional groups present in the compound. The third harmonic optical nonlinearity test was carried out using z‐scan technique. The single crystals were grown using slow evaporation solution growth technique. Optical absorption studies reveal that the crystal is transparent in the entire visible region and absorption (around 364 nm) takes place in the UV‐region. The single‐crystal XRD studies were carried out, and it was found that the compound crystallizes in the monoclinic system with a space group P21/c. The observed lattice parameters are a = 16.6170(6) A b = 7.6180(5) A c = 10.9280(11) A and V = 1338.47(17) A3.

Linear and NLO properties of an organic single crystal

Organic compound of 1-(4-methoxyphenyl)-3-(2-methoxy 5-bromophenyl)prop-2-en-1-one [MMBPP] with molecular formula C16H11BrO3 was synthesized using Schmidt condensation method. A FT-IR spectrum was recorded to identify the various functional groups present in the compound. The single crystals were grown using slow evaporation solution growth technique. The high quality transparent crystals up to a size 10×7×5 mm3 are obtained with in fifteen days. UV-Visible spectrum reveals that the crystal is transparent in the entire visible region. The single crystal XRD study shows that the compound crystallizes in orthorhombic crystal system with a space group P212121 and the observed cell parameters are a =7.6095(13) A, b =13.049(2) A, c = 15.525(3) A, Volume 1541.6(5) A3. The third order Nonlinearity was confirmed by Z-scan technique and non-linear parameters were determined.

Nonlinear optical studies of a novel pyrazoline

A novel pyrazoline, 3-(phenyl)-5-(4-hydroxyphenyl)-1-(2, 4-dinitrophenyl)-2-pyrazoline (PHDP) was synthesized using standard method and its chemical structure was confirmed using FTIR studies. The linear and non linear optical properties of the compound were studied using UV-Vis and Z-scan techniques. UV-Vis spectrum shows that the compound is transparent in the visible region and absorption in the UV region. The z-scan study shows that the compound possesses third and higher order optical nonlinearity. The calculated optical absorption cross sections indicate that the operating nonlinear mechanism is reverse saturable absorption type. The real part of the third-order nonlinear optical susceptibility χ3 was estimated and the closed aperture data shows that PHDP possess negative nonlinearity.

Third Order Optical Nonlinearity of a Pyrazoline Derivative

A new pyrazoline derivative 3‐phenyl‐5‐(4‐N,N‐dimethylaminophenyl)‐1H‐2‐pyrazoline (PDHP) was synthesized using standard method. The structure of the compound was established based on 1H NMR spectrum. The third‐order optical nonlinear properties of PDHP compound were measured using nanosecond Z‐scan method The measured nonlinear absorption coefficient β is 0.27×10−10 m W−1. The magnitude of third order susceptibility is Reχ(3) = =19.94×10−13 esu and Imχx(3) = 5.85×10−13 esu. These experimental results reveal that the PDHP may be a good candidate for optical limiting applications due to its reverse saturated absorption phenomenon