Carbon benzene interaction, attractive

In this study, an extraction approach to the problem of attractive interactions in Green River (Mahogany Zone) oil shale resulted in the preferential dissolution of both carbonate and silicate minerals. As the results in Table IV indicate, the interfacial organic layer between kerogen and the inorganic mineral matrix was also simultaneously separated. Since the majority of the bitumen was removed in the initial benzene/... 

Chloroform shows a significant binding interaction with benzene, but carbon tetrachloride does not. Predict the preferred geometry for the interaction and describe the physical nature of the attraction between the two molecules. 

The CH/tt interaction is very weak in most cases. The interaction energies of benzene complexes with methane, ethane and ethylene are around -2 kcal/mol, as summarized in Table 6. The attraction is enhanced when electronegative substituents (chlorine and fluorine atoms) are attached to the carbon atom of the C - H bond [112]. The interaction energy of the benzene-chloroform complex (- 5.6 kcal/mol) is considerably greater than that of the benzene-methane complex (- 1.5 kcal/mol). The enhancement of the attraction was explained by the increased electrostatic interaction. The substituent increases the positive charge on the hydrogen atom of the C - H bond and thereby increases the attractive electrostatic interaction. The electrostatic energy in the benzene-chloroform complex (- 2.4 kcal/mol) is 2.2 kcal/mol... 

Besides benzene and naphthalene dimers, various earbon materials have also attracted attentions in the context of r-stacking interactions. The most frequently targeted systems are nanotube and graphene for their electronic, adsorptive, and reactive properties. So far, many DFT studies have been reported especially for single-walled carbon nanotube (SWCNT) and graphene in the fields of both quantum chemistry and solid state physics. 

The attractive interactions of all three compounds are dominated by dispersion interactions (parameter a), while size affects parameter b. Toluene has the highest values for a and b. Toluene has seven carbon atoms, whereas the other molecules have only six. This results in the largest polarizability as well as the largest size. Cyclohexane s electrons are freer to move than the tight resonance structure exhibited by benzene. This leads to a greater polarizability than benzene. In fact the magnitude of dispersion forces is closer to toluene than benzene. Finally, cyclohexane has a three-dimensional structure, while the other two are planar and flat Hence, the constant b, representative of size, is almost as large for cyclohexane as it is for benzene. 

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