فهرست مقالات PCM model

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  1 - Theoretical study of the solvent effects on the thermodynamic functions of Alanine and Valine Amino Acids
  farideh Keshavarz Rezaei
  Using Gaussian 03, software the thermodynamic functions such as Gibbs free energy, G, Enthalpy, H, and Entropy, S, of Alanine and Valine amino acids were theoretically studied at different solvents. First, the Density Functional Theory (B3LYP) level with 3-21G, 6-31G چکیده کامل

  Using Gaussian 03, software the thermodynamic functions such as Gibbs free energy, G, Enthalpy, H, and Entropy, S, of Alanine and Valine amino acids were theoretically studied at different solvents. First, the Density Functional Theory (B3LYP) level with 3-21G, 6-31G and 6-31+G basis sets were employed to optimization of isolated Alanine and Valine amino acids in the gas phase. Moreover, Vibrational frequencies were calculated in gas phase on the optimized geometries at the same level of theory to obtain the thermodynamic functions such as Gibbs free energy, G, Enthalpy, H, and Entropy, S,. Then, the calculation about the solvent effects on the thermodynamic functions of Alanine and Valine amino acids were performed for the various solvents (Water, Methanol and Ethanol) by using self consistent Reaction-Field (SCRF=PCM) model at B3LYP/6-31+G. Thermodynamically analysis shows the relative Gibbs free energy changes, G, Enthalpy changes, H, are negative values but the Entropy changes, S, are positive values for Alanine and Valine amino acids. Also, the results shows, with increasing of dielectric constant of solvents the stability of considered amino acids increases. پرونده مقاله
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  2 - A Theoretical Study of the Stability and Dielectric Constants of Molybdate-Phosphonic Acid Complex
  M.H. Ghorbani R. Fazaeli A. Ghoorchian
  In this work, we investigated the stability of Molybdate-Phosphonic Acid (MPA) complex by density functionaltheory (DFT) computations in six solvents with the dielectric constant ranging from 1.92 to 10.36. The methodsare used for calculations are B3LYP and B3PW9 I that چکیده کامل

  In this work, we investigated the stability of Molybdate-Phosphonic Acid (MPA) complex by density functionaltheory (DFT) computations in six solvents with the dielectric constant ranging from 1.92 to 10.36. The methodsare used for calculations are B3LYP and B3PW9 I that have been studied in two series of basis sets: D95nand6-31+G (d,p) for hydrogen and oxygen atoms; LANL2DZ for Mo and Phosphorus. Considering the effect ofsolvent, using PCM solvent model, the stability of MPA complex when passing to higher dielectric constants iscalculated. Predicted geometry and relative stability are discussed. Equilibrium geometry in the groundelectronic state energy has been calculated for 1:1 complex. The best results for energetic and geometricalground state in different of used solvents were obtained with Becke3LYP calculations. An increasingstabilization of MPA when increasing the dielectric constant in a continuum solvent model. پرونده مقاله
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  3 - Solvent Effect Study on the Stability Energies of Glycine, Alanine and Valine Amino Acides
  F. Keshavarz Rezaei A. Taherpour M. Aghaie
  Glycine, Alanine and Valine are taken as amino acids with an equal polar head and with thedifference in the length of hydrocarbon chains. The structural optimizations show the results of theisolated Glycine, Alanine and Valine in the gases phase, at the Hartree-Fock lev چکیده کامل

  Glycine, Alanine and Valine are taken as amino acids with an equal polar head and with thedifference in the length of hydrocarbon chains. The structural optimizations show the results of theisolated Glycine, Alanine and Valine in the gases phase, at the Hartree-Fock level by means ofSTO-3G,3-21G, 6-31G and 6-31+G basis sets. The calculations were performed for the ten (1-10)solvents using PCM model method at HT/6-31+G and then the dielectric effects of the surroundingwere analyzed. The solvent effect on the stability of Glycine, Alanine and valine molecules wasdiscussed. پرونده مقاله
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  4 - Theoretical Study of the Solvent Effect on the Stability Energies of Pyrazole and Pyrazoline
  Farideh Keshavarz Rezaei
  Using the Density Functional Theory (DFT) level by means of 3-21G, 6-31G and 6-31+G (d) basissets, the structural optimization of isolated Pyrazole and Pyrazoline was done in the gas phase. Then,the calculation about the solvent effect on the stability energies of Pyraz چکیده کامل

  Using the Density Functional Theory (DFT) level by means of 3-21G, 6-31G and 6-31+G (d) basissets, the structural optimization of isolated Pyrazole and Pyrazoline was done in the gas phase. Then,the calculation about the solvent effect on the stability energies of Pyrazole and Pyrazoline wasperformed for the ten solvents using PCM model method at B3LYP/6-31+G(d) and then the dielectriceffects of the surrounding and the solvent effects on the stability energies of Pyrazole and Pyrazolinemolecules were discussed. پرونده مقاله