Journal of Physical and Theoretical Chemistry
Volume:11 Issue: 1, Spring 2014

Chemical hardness (), absolute electronegativity (), and electrophilicity () have importantapplications in inorganic chemistry. These concepts are defined quantitatively as Where I is the ionization energy and A is the electron affinity. In thisstudy, graphical method was used to see the relation of electron configuration with chemicalhardness, absolute electronegativity and electrophilicity. For this purpose, sequential ionization ofatoms were considered. In this method, chemical hardness, absolute electronegativity, electrophilicityand effective nuclear charge (Z*) were calculated for all ions formed with sequential ionization of anatom and chemical hardness, absolute electronegativity and electrophilicity with respect to effectivenuclear charge were illustrated in the graphs. Besides, the same charged ions were considered inorder to see more clearly relationship with electron configuration of these three features becausecharge is effective on chemical hardness, absolute electronegativity and electrophilicity. Likewise,chemical hardness, absolute electronegativity and electrophilicity values were calculated and graphsof these three features were plotted with respect to atomic number (Z). As to conclude, it was proventhat chemical hardness, absolute electronegativity and electrophilicity increase in some specificelectron configurations and this means that configuration effect is a more effective factor than radiusand charge.

In this research, a semi empirical approach has been suggested for calculating the activation energyof unimolecular thermal decomposition of vinyl ethers yielding saturated products. The calculationprocedure is based on the use of molecular mechanics (MM) methods. These methods which involvethe construction of the transition state for a molecule mainly consider the formation of a “HydrogenBridge” between the alkyl and vinyl groups and also use the Lennard - Jones potential. Theactivation energy of the decay is calculated as the difference between bond energy of the Hydrogenatom jumping from the alkyl group to the vinyl group, and the strain energy of the molecule due tothe formation of the transition state (TS). A new semi empirical method for computing the activationenergy at spontaneous decay of vinyl ethyl ether (VEE), vinyl propyl ether (VPE) and vinyl butylether (VBE) molecules has been developed. It allows calculating the values of the activation energyby simple procedures. The obtained results for the decay of vinyl ethers are in good agreement withthe known experimental data in the literature.

In this work, the structural and electronic properties of folic acid molecule on functionalized (7,0)zigzag single-walled carbon nanotube was studied in gas phase on the basis of density functionaltheory (DFT). Furthermore, covalent interaction of folic acid with single-walled carbon nanotube wasinvestigated and its quantum molecular descriptors and binding energies were calculated. The DFTB3LYP/6-311G(d) calculations revealed that the binding energies of single walled carbon nanotubewith folic acid have negative values and decrease with increasing in the number of functionalization.

In this research, the physico-chemical water quality parameters and the effect of climate changes onwater quality is evaluated. During the observation period (5 months) physico-chemical parameterssuch as water temperature, turbidity, saturated oxygen, dissolved oxygen, pH, chlorophyll-a, salinity,conductivity, and concentration of total nitrogen (nutrient level) as main pollutant factor have beenmeasured in Iran from September to February 2013 in the Amirkabir dam area. Moreover, anadaptive neuro fuzzy inference mechanism (ANFIS) is designed for the sake of modeling andprediction. In order to learn the proposed ANFIS mechanism a Quantum behave particle swarmoptimization (QPSO) is employed. The proposed ANFIS architecture has nine-input and one outputin which the physico -chemical parameters of water and total nitrogen have been considered as inputand output of the proposed ANFIS, respectively. In this paper to reduce the noise and measurementerrors a wavelet transform strategy is utilized.

In this study, geometrical optimizations of Clonidine Drug were carried out with the HF/6-31g basissets .Then, drug was put covalently to carbon nanocone with (5, 1) structure and a length of 150A. Weuse chem Office software and hyper chem at the end data will be presented as tables and Figs.Simulation was done in MM+, AMBER and OPLS force fields by Monte Carlo method. Threeimportant energy parameters – Potential Energy, Kinetic Energy and Total Energy- calculated in fivedifferent simulating temperatures (308, 310, 312, 314 and 316 Kelvin) were used for computation andgood results were obtained.

The doping reaction of truncated boron nitride and carbon nanotubes with aluminium atom wastheoretically investigated. The AM1, PM3, and PM6 semiempirical methods have been used toevaluate the thermochemistry of doping reactions of single walled boron nitride nanotubes andcarbon nanotubes. The enthalpy changes, Gibbs free energy changes, and entropy changes of studieddoping reactions were evaluated at different temperatures. The AM1 and PM6 results showed Aldopingreaction of (8,0)CNT is exothermic and spontaneous . Among the studied armchair and zigzagnanotubes, AM1 and PM6 calculations reveal that (8,0)CNT is the best candidate for Al-dopingreaction.