An integrated approach to the modelling of chemical reactors, particularly catalytic ones is presented. The modelling approach starts from quantum-chemical calculations, mechanistic hypothesis, derivation of kinetic expressions in order to achieve an appropriate kinetic model. The model parameters are determined by regression analysis and the complex behaviour of fixed bed reactors, including c...

A classical interaction model for the calculation of molecular polarizabilities has been investigated. The model is described by atomic capacitancies, polarizabilities, and a parameter related to the size of the atom, where one set of parameters has been employed for each element. The model has been parameterized for the elements H, C, N, O, F, and Cl from quantum chemical calculations of the m...

At the present study, different properties of Sarin with the formula [(CH3)2CHO]CH3POF was studiedin gas phase. Geometrical optimizations of Sarin, single point calculation, NMR and Electricalparameters were carried out in gas phase with the Hartee -Fock method coupled to 6-31g* basis setsfor all atoms. The results obtained from a comparison between tables and charts came up fordiscussion and a...

A parameterization has been performed of the biologically important sterols cholesterol, ergosterol, and lanosterol for the CHARMM27 all-atom molecular mechanics force field. An automated parameterization method was used that involves fitting the potential to vibrational frequencies and eigenvectors derived from quantum-chemical calculations. The partial charges were derived by fitting point ch...

We propose a quantum trajectory analysis of a scheme to measure the states of a coupled-dot device (qubit) where there is a fluctuating energy gap Δ between the two states. The system consists of the qubit and a readout dot coupled to source and drain leads. The tunnel rate through the detector is conditioned by the occupation number of the nearer quantum dot (target) of the qubit and therefore...

The research in new organic π-conjugated molecules with specific properties has become one of the most interesting topics in fields of materials chemistry. These materials are promising for optoelectronic device technology such as solar cells. On the other hand, the use of low band gap materials is a viable method for better harvesting of the solar spectrum and increasing its efficiency. The Co...

Modern quantum chemistry can make quantitative predictions on an immense array of chemical systems. However, the interpretation of those predictions is often complicated by the complex wave function expansions used. Here we show that an exceptionally simple algebraic construction allows for defining atomic core and valence orbitals, polarized by the molecular environment, which can exactly repr...

In this research, the quantum mechanics calculations were carried out to elucidate the adsorption behavior of metronidazole drug on the surface of pristine as well as doped C60 fullerene with Si, B and Al using density functional theory (DFT) at B3LYP/6-31G(d,p) level. After optimization of the structures, various parameters such as HOMO and LUMO energies, gap energy, adsorption ener...