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Intermolecular interaction energies for molecular dimers of benzene, indene, naphthalene, phenanthrene, cholesterol and glycyrrhetinic acid have been calculated according to the CVFF empirical force field of the DISCOVER program. The parallel orientations (side by-side) turned out to be the energetically most favourable ones, in agreement with the parametrization of Gay–Berne potentials. The energies of the T-shape and in-plane (end-to-end) orientations of the entirely asymmetric molecules cholesterol and glycyrrhetinic acid depend strongly on the actual atomic positions. This shows the extent to which the shape and charges of molecules determine all possible orientations and interaction energies in molecular ensembles.

We calculate here the Raman frequencies of some lattice modes as a function of pressure at constant temperatures for the solid and liquid phases of benzene. The observed data for the molar volume from literature is used to calculate the Raman frequencies through the mode Grüneisen parameter in benzene.

Our calculated frequencies are in good agreement with the observed data when the mode Grüneisen parameter is taken as a constant at one particular pressure in solid benzene.

It is shown here that the Raman frequencies can be calculated from the volume data, as demonstrated for benzene here.

Tungsten carbide nanoparticles were synthesized successfully by DC arc discharge plasma process with 23 A discharge current at atmospheric pressure, in which tungsten positive electrode reacted with carbon black produced from the benzene cracking. The XRD results indicate that the samples consist of carbon black, WC and W₂ C. The TEM micrographs show that the tungsten carbide particles range from 3 to 7 nm in size, and are composed of WC and W₂C.

This paper presents the results of a study of the dielectric constant of solutions of a polar liquid in a nonpolar solvent: chlorobenzene–benzene, chlorobenzene–hexane. The measurements were carried out at a wavelength $\lambda =12.80$cm in the temperature range from $-80^{\circ }$C to $20^{\circ }$C. The studies were carried out using the dielectric spectroscopy method. This method allows a more detailed study of the dielectric properties of the objects of study due to the large equilibrium (“static”) dielectric constant of the object. The temperature dependence of the dielectric relaxation time of molecules in the liquid and solid states of the studied solutions is determined. It has been established that with increasing concentration (0.300, 0.562, 0.794, 1.000 for a chlorobenzene–hexane solution and 0.179, 0.368, 0.567, 0.778, 1.000 for a chlorobenzene–benzene solution) of the halogen substituent, the relaxation time increases. The measurement results of dielectric constant ${\epsilon }^{\prime }$ and absorption coefficient ${\epsilon }^{\prime \prime }$ obtained for concentrated solutions chlorobenzene–benzene, chlorobenzene–n–hexane at wavelengths $\lambda =12$, 80 and $\lambda =3,26$cm at temperature $20^{\circ }$C are given in the paper. The static dielectric constant is obtained at a frequency of 1MHz. The obtained experimental values ${\epsilon }^{\prime }$, ${\epsilon }^{\prime \prime }$ and ${\epsilon }_0$ of investigated systems in (${\epsilon }^{\prime }$, ${\epsilon }^{\prime \prime }$) plane locate on the semi-circle the center of which is on ${\epsilon }^{\prime }$ axis. In this case, the high-frequency limit value of $\epsilon \infty$ dielectric coefficient exceeds the corresponding n₂ refraction index square. The macroscopic and molecular relaxation times are calculated on the base of experimental data. The thermodynamic quantities characterizing the process of dielectric relaxation are calculated for solutions of chlorobenzene–benzene, chlorobenzene–hexane. It has been determined that the height of the potential barrier separating the two equilibrium positions of a polar molecule is greatest in the state of a pure polar liquid and decreases with dilution in a nonpolar solvent.

A new approach for the development of nano-sized spectroscopic-based early-warning sensors using molecular electrostatic potentials (MEP) and molecular vibronics (MV) was presented. The use of MEPs allow us to sense and detect specific molecules in elaborated arrays of logical gates which provide the signature of the trapped species and a decision signal of the results of the sensing operation. Molecular vibronics is used to activate/deactivate, control and program the detection process as well as to transmit the information to and from nano-micro interfaces that allow the interaction with microelectronic systems. In order to develop this scenario, it is needed to explain the exact reasons, from an atomistic point of view rather than using phenomenological models the effects of molecules on nanoclusters. We present here a study of silicon-phenyl complexes.