Growth, Optical and Dielectric Studies on Pure and L-Lysine Doped KDP Crystals

Optically good quality single crystals of pure and L-lysine monohydrochloride-doped KDP crystals have been grown by a slow evaporation method. The grown crystals have been subjected to optical and dielectric studies. The UV-Vis spectrum shows the transmitting ability of the crystals in the entire visible region and transmittance percentage is increased for the doped KDP crystals. From the dielectric study, it is found that the dielectric constant and the dielectric loss of L-lysine-doped KDP crystals were lower than the pure KDP crystals. Hence L-lysine-doped KDP crystals are found to be more beneficial from an application point of view as compared to pure KDP crystals

3-Nitrophenol–1,3,5-triazine-2,4,6-triamine (2/1)

The asymmetric unit of the title compound, C3H6N6·2C6H5NO3, contains one melamine and two 3-nitrophenol molecules. The mean planes of the 3-nitrophenol molecules are almost orthogonal to the plane of melamine, making dihedral angles of 82.77 (4) and 88.36 (5)°. In the crystal, molecules are linked via O—H...N, N—H...N and N—H...O hydrogen bonds, forming a three-dimensional network. The crystal also features weak C—H...π and π–π interactions [centroid–centroid distance = 3.9823 (9) Å]

Growth, Optical and Dielectric Studies on Pure and L-Lysine Doped KDP Crystals

Optically good quality single crystals of pure and L-lysine monohydrochloride-doped KDP crystals have been grown by a slow evaporation method. The grown crystals have been subjected to optical and dielectric studies. The UV-Vis spectrum shows the transmitting ability of the crystals in the entire visible region and transmittance percentage is increased for the doped KDP crystals. From the dielectric study, it is found that the dielectric constant and the dielectric loss of L-lysine-doped KDP crystals were lower than the pure KDP crystals. Hence L-lysine-doped KDP crystals are found to be more beneficial from an application point of view as compared to pure KDP crystals

Thermal decomposition behaviour of bis(4-nitrophenol)-2,4,6-triamino-1,3,5-triazine monohydrate

Thermal decomposition behavior of bis (4-nitrophenol)-2,4,6-triamino-1,3,5-triazine monohydrate (BNPM) has been studied by means of thermogravimetric analysis at three different heating rates 10, 15 and 20°C min¯¹. Non-isothermal studies of BNPM have revealed that the decomposition occurs in three stages involving dehydration and decomposition. The values of effective activation energy (E_{a}), pre-exponential factor (A) of each stage of thermal decomposition for all heating rates were calculated by model free methods: Arrhenius, Flynn-Wall, Friedman, Kissinger and Kim-Park method. A significant variation of effective activation energy (E_{a}) with conversion (α) indicates that the process is kinetically complex. The linear relationship between the A and E_{a} values was well established (compensation effect). Dehydration stage was governed by the Avrami-Erofeev model (A2) and decomposition stages were governed by the Avrami-Erofeev model (A4)

Vibrational Spectroscopic and Computational Studies on Bis(2-aminopyridinium)fumarate - Fumaric Acid (1:1) Complex

The new vibrational and computational studies on bis(2-aminopiridinium) fumarate - fumaric acid (1:1) complex have been made. The molecular geometry, vibrational frequencies and intensities of vibrational bands have been interpreted with the aid of structure optimization based on density functional theory (B3LYP) method with 6-311++G(d,p) basis set. The highly occupied-lowly unoccupied molecular orbital energies and chemical reactivity of the molecule have been calculated with time-dependent density functional theory approach. Stability energies of the molecule have been studied using natural bond orbital analysis. The predicted nonlinear optical properties of the title compound are much greater that those of urea. In addition, the molecular electrostatic potential surfaces and thermodynamic properties were calculated

Kinetics and Mechanical Studies of Melaminium bis(trichloroacetate) dihydrate

The thermal decomposition kinetics of melaminium bis(trichloroacetate) dihydrate (MTCA) has been studied by thermogravimetry and derivative thermogravimetry techniques using non-isothermal experiments at three different heating rates 10, 15, and 20°C $\text{min}^{-1}$. Non-isothermal studies of MTCA revealed that the decomposition occurs in three stages involving dehydration and decomposition. The apparent activation energy $(E_{a})$ and the pre-exponential factor (ln A) of each stage of thermal decomposition at various linear heating rates are calculated using Flynn-Wall, Friedman, Kissinger, and Kim-Park method. A significant variation of effective activation energy $(E_{a})$ with conversion $(α)$ indicates that the process is kinetically complex. The linear relationship between the A and $E_{a}$ values is well established (compensation effect). Isothermal kinetics of thermal decomposition of MTCA was found to obey Avrami-Erofeev's (A4) and power law (P3) equations. In addition to the above, mechanical properties have been estimated by Vicker's microhardness test for the grown crystal

Density Functional Theoretical Computational Studies on 3-Methyl 2-Vinyl Pyridinium Phosphate

The molecular structure of 3-methyl 2-vinyl pyridinium phosphate (3M2VPP) has been optimized by using Density Functional Theory using B3LYP hybrid functional with 6-311++G (d, p) basis set in order to find the whole characteristics of the molecular complex. The theoretical structural parameters such as bond length, bond angle, and dihedral angle are determined by DFT methods and are well agreed with the single crystal X-ray diffraction parameters. Theoretical vibrational, highest occupied molecular orbital - lowest unoccupied molecular orbital (HOMO-LUMO), natural bonding orbital (NBO), and electrostatic potential (ESP) analyses have also been performed. Based on the potential energy distribution (PED), the complete vibrational assignments, analysis, and correlation of the compound’s fundamental modes have been determined. Natural bonding orbital (NBO) analysis is used to evaluate the intramolecular charge transfer and hyper-conjugative interaction of the molecule. B3LYP/6-311++G (d, p) basis set determines the electronic properties such as HOMO–LUMO energies and is used to understand the kinetic stability and chemical reactivity of the studied compound. Molecular electrostatic potential (MEP) is used to investigate the electron density distribution and chemical reactive sites of 3M2VPP. The dipole moment, total polarizability, and the first-order hyperpolarizability calculations have been carried out for the studied molecule. Hirshfeld surface analysis has been done to study the intermolecular interactions in the studied complex