Growth and Characterization of New Semi-Organic L-Asparagine Potassium Di-Hydrogen Phosphate Crystals

Abstract

The studies on the growth and characterization of a new semi-organic non-linear optical crystal, L-asparagine potassium dihydrogen phosphate have been successfully carried out by slow evaporation technique using deionized water as a solvent. The grown crystal is characterized by powder X-ray diffraction analysis and FT-IR analysis. The results of X-ray diffraction analysis showed that it possess orthogonal structure having lattice parameters a = 5.582 Å, b = 9.812 Å and c = 11.796 Å, α = β = γ = 90° and V = 514 Å 3. The fourier transform infrared spectroscopy of L-asparagine potassium dihydrogen phosphate crystal were recorded between wave-number 4000 to 400 cm-1 showed very weak bands appearing around 1232 and 1147 cm-1 are due to P-O-H stretching and bending. The observed broad intense band in 3385-3119 cm-1 region is assigned to NH stretch of NH2 vibration of L-asparagine potassium dihydrogen phosphate molecule. The CH2 vibration of the amino acid shows its peak at 2945 cm-1. The combination band observed at 2149 cm-1 is due to asymmetric NH3 + vibration at 1643 cm-1 and NH2 + tensional oscillation at 512 cm-1 and optical transmission spectral analysis. The lower cut off wavelength of L-asparagine potassium dihydrogen phosphate crystal occurs at 198 nm and it reveals that the material has good optical transparency in the entire visible region. The results of hardness test showed that the presence of dopant has enhanced the mechanical strength of the L-asparagine potassium dihydrogen phosphate crystals and the second harmonic generation of L-asparagine potassium dihydrogen phosphate crystals was tested using Kurtz and Perry method also showed good results.

Characteristics and quality of grown potassium thiourea iodide crystal for second harmonic generation

“…Our results resembles with the earlier reported results in case of other crystals [16,17]. The frequency dependent dielectric behavior of the PTI crystal is due to the contribution of electronic, ionic, dipolar and space-charge polarizations [17,18]. The mechanism of polarization may be considered like a conduction process.…”

“…On the basis of this comparison of our result for the case of variation of dielectric constant with temperature, refer to Fig. 5a, seems to be interesting to indicate improvement in crystal quality with respect to others as reported earlier by Neelakantaprasad et al [18]. This argument is also supported by the almost temperature independence of dielectric loss factor at high frequency as shown in the Fig.…”

“…5a is that the dielectric constant was observed in decreasing order with the rise of temperature in the higher frequency range above 400 Hz. However, in an earlier reported case of the same PTI crystal, an opposite behavior was observed with the rise of temperature that the capacitance/dielectric constant increases [18]. On the basis of this comparison of our result for the case of variation of dielectric constant with temperature, refer to Fig.…”

“…Finally after examine the results of our all type of studies it is also concluded that physical properties of the grown crystal are not much affected in this case by the presence of impurities and defects which further conclude that potassium thiourea iodide is a promising material for photo induced SHG in laser physics. Although on the basis of the literature survey it was found that up to now this material is less studied [2,3,18]. Therefore, the study on PTI crystal is more needed to exploit its potentiality regarding its use in optoelectronic devices.…”

Growth and Characterization of Promising Nlo Crystal: Meta Nitroaniline

“…The spectrum further indicates that the crystal has a wide optical window from 280 nm to 1100 nm. The transparency in the entire visible region shows that this material is a best suitable candidate for optoelectronic application 19,20 . …”