Practical synthesis of β-isothiocyanato ketones from chalcones

Practical synthesis of 1,3-diaryl-substituted 3-isothiocyanatopropan-1-ones based on the reaction of chalcones with thiocyanic acid generated in situ by treatment of thiocyanate ammonium with dilute sulfuric acid has been developed.     

Color Indicator System for Acid–Base Titration in Aqueous Micellar Solutions of the Cationic Surfactant Tridecylpyridinium Bromide

Acid–base properties of sulfophthalein indicators were studied in aqueous micellar solutions of the cationic surfactant tridecylpyridinium bromide (TDPB). A multiple linear regression was proposed for predicting protolytic properties of the reagents of this series in micellar TDPB solutions. Conditions were found for the titrimetric determination of long-chain aliphatic carboxylic acids with the use of Xylenol Blue for detecting the titration end point.     

Parameterized Effective Potential for Excited States and Its Application to the Calculation of Transition Dipole Moments

Optics and Spectroscopy - A parameterized effective potential method that was proposed earlier for the ground state has been developed for excited states with symmetry of the ground state. Various...     

Dipole order and stability of the ferroelectric and antiferroelectric states in lead zirconate

Coordination polyhedra have been constructed for Pb in a PbZrO₂ crystal. It is shown that there is no geometric similarity between the displacements of the lead ions and the dipole moments responsible for the antiferroelectricity, which is generally assumed in calculations of the relative stability of the antiferroelectric and ferroelectric phases in pure PbZrO₃ and its solid solutions. The latest data on the atomic structure of phases with the Pbam and Cm2m space groups are used to refine conventional reasoning on the dipole motif of this crystal. It is shown that in the point-dipole model, the antiferroelectric dipole configuration is energetically more favorable than the ferroelectric, which is consistent with the observation conditions for both phases. Fiz. Tverd. Tela (St. Petersburg) 40, 1324–1327 (July 1998)     

Phase transitions induced in NaNbO3 crystals by varying the direction of an external electric field

The anisotropic behavior of the electrostatic field characterizing the phase transition from an antiferroelectric state to a ferroelectric state is studied for the first time with NaNbO₃ as an example. Structural changes taking place in the crystal as the direction of the electrostatic field is varied are studied and electrostatic field magnitude-direction phase diagrams are determined. Fiz. Tverd. Tela (St. Petersburg) 39, 1084–1087 (June 1997)