Study of depolarized Rayleigh scattering in liquid benzene derivatives

The spectrum of the depolarized Rayleigh line has been measured for benzene, toluene, fluorobenzene and bromobenzene (at 22°c). The central part of the spectrum was measured at high resolution using a piezoelectric scanned Fabry-Pérot with a maximum free-spectral range of about 20 cm^-1. The entire spectrum was also measured with a monochromator extending the region to 100 cm^-1. The results from the two techniques were combined in order to deduce the correct line shape from which we were able to determine two relaxation times τ1 and τ2.     

Adsorption of nonpolar benzene derivatives on single-walled carbon nanotubes

The adsorption of benzene, toluene, and chlorobenzene on single-walled carbon nanotubes (SWCNTs) with and without acid oxidation was conducted to investigate the influences of derivative groups on benzene rings and functional groups from SWCNTs on adsorption by SWCNTs. The SWCNTs of high purity were chosen and moderate acid oxidation was performed so that the surface physical properties remained unchanged after acid oxidation and the influences of acid oxidation on adsorption were only contributed from the modification of the surface chemistry of SWCNTs. The oxygen-containing surface groups introduced by acid oxidation obstructed the interactions between functional groups of nonpolar benzene derivatives and C-rings of SWCNTs significantly. The dispersive interaction between the partially positive H⁺ of the methyl group and the oxygen-containing surface groups slightly increased the adsorption of toluene on oxidized SWCNTs at high solution pH. The thermodynamic of adsorption was also studied at different temperatures.     

Sonochemical polymerization of benzene derivatives: the site of the reaction

Sonochemical polymerization of benzene and halogen-substituted benzenes has been studied. The difference of absorption spectra of polymerization products can be explained qualitatively using bond energies of the primary products. The relative rate constant of the polymerization reaction is apparently proportional to the inverse of the vapour pressure of the liquids. Using this relation, we analysed the relative rate constant of the polymerization in benzene/chrolobenzene mixtures. From this, we conclude that sonochemical polymerization proceeds in the vapour phase of a bubble.     

CASSCF calculations of triplet state properties: applications to benzene derivatives

We illustrate the capability of the complete active space self-consistent field method by Roos and co-workers for calculations of triplet state properties. We report phosphorescence lifetimes, zero-field splitting parameters, and nuclear quadrupole coupling constants for the lowest triplet state of a variety of benzene derivatives.     

Calculation of derivatives of spectral functions in solids

Derivatives of spectral functions play a central role in the calculation of modulation spectroscopy. The general expressions for these derivatives are obtained. Transition probabilities and lifetime effects are also treated and incorporated in the general framework of the Brillouin zone integration of these derivatives.     

Calculation of lower excited electronic levels of benzene with the Green's function method

The Green's function method for the calculation of orbital energies which was discussed in a preceding paper is applied to the calculation of the lower excited states of the benzene molecule. The Dyson equation for the polarization (particle—hole) propagator is derived with the diagrammatic technique and the secular equation which gives poles of the polarization propagator is solved. The random phase approximation is not used in our calculation. Theoretical results are discussed in comparison with experimental data. Using a model system of two π-electrons, our method is compared with the equations-of-motion method.     

The electrical conductivity of benzene and its monohalide derivatives in an ultrasonic field

Ultrasonics has found increasing use in instrumentation techniques in recent years as a means of studying the physicochemical properties of materials and articles, and also as a means of accelerating technological processes in various branches of the national economy. At the same time not enough use is made of the possibilities of ultrasonics in many branches of science and technology. These include the study of the effect of ultrasonics on the electrical conductivity of electrolytes, liquid semiconductors, and dielectrics. Available published information on these topics [1 – 5] is scant; the effects observed have been described only qualitatively and need further study.The present paper is devoted to a study of the effect of ultrasonic vibrations (frequency 1.25 Mc, intensity 2 W/cm²) on the electrical conductivity of benzene in an electric field of 5 kV/cm, and on the electrical conductivity of chlorobenzene, bromobenzene, and iodobenzene in a field of 1 kV/cm in the precavitation region. An interpretation of the experimental results is offered.     

Calculation of ionic crystal-metal interaction characteristics

The adhesion properties of composites based on simple metals and ionic crystals with an NaCl lattice are investigated using the electron density functional method. Corrections due to the nonuniformity of the electron density and the discrete nature of the crystal structure are taken into account. The interphase energy, the adhesion energy and the adhesion interaction forces are calculated as a function of the distance between the surfaces of the contacting materials.     

Calculation of plasma characteristics of the sun

The ionization level and free electron density of most abundant elements (C, N, O, Mg, Al, Si, S, and Fe) in the sun are calculated from the centre of the sun to the surface of the photosphere. The model and computations are made under the assumption of local thermodynamic equilibrium (LTE). The Saha equation has been used to calculate the ionization level of elements and the electron density. Temperature values for calculations along the solar radius are taken from references.     

Calculation of some characteristics of substituted benzenes

Compounds of the C₆H₅XY₁Y₂ type have been examined, and the dependence of energy and wave functions ona _Y, ß_XY and ß_CX has been studied. Numerical calculations have been carried out and tables compiled.In conclusion the authors would like to thank N. A. Prilezhaev and V. I. Danilov, who helped us daily in carrying out this work.     

Effect of hydrostatic pressure on the electric permittivity and the density of liquid benzene derivatives

The pressure dependence of the electric permittivity and the density of a series of benzene derivative liquids was measured up to 100 MPa. [(?P ? ?¹)/?p]/[(dP ? d¹)/dP] was found to be linearly dependent on the dipole moment of the liquids.