Hyperpolarizability calculation and kinetic effect of impurities on LVP

• Hyperpolarizability of the LVP crystal was estimated by DFT method.
• Detailed knowledge of the solution crystallization in the absence or in presence of impurities can be obtained.
• Two-dimensional nucleation growth mechanism and surface morphologies are discussed.

In order to investigate microscopic second order nonlinear optical properties of L-valinium picrate (LVP) crystals, the molecular dipole moment, polarizability, and first hyperpolarizability are estimated by density functional theory (DFT). Apart from that, a quantitative study using Atomic force microscopy (AFM) combined with crystal growth experiments on the effects of impurities (magnesium and copper) on LVP is presented. Two-dimensional (2D) nucleation growth mechanism and typical surface morphologies are described and discussed. In the presence of impurities, the decreasing of the size of 2D islands is probably incurred by the reducing of the step kinetic coefficient. From the supersaturation dependence of the normal growth rate, the effective step edge free energies are evaluated as γ0 = 2.90 kT, γMg = 2.76 kT, γCu = 2.95 kT.

Molecular structure for LVP.Figure optionsDownload as PowerPoint slide