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محاضرات مقياس مخبر السمعي البصري  ماستر السداسي الثاني تخصص سمعي بصري   الدكتور بن دريس أحمد

عزيزي الطالب تجد في الملف المدرج أسفله ملخص عن محاضرات المقياس إضافة للمحاضرات التي قمنا بتقديمها قبل الحجر

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Avatar SALIH HACINI
par SALIH HACINI, lundi 11 mai 2020, 14:10
Tout le monde sur ce site

TD  Halogénation

 
Tout le monde sur ce site

Chapitre III  Halogénation

Partie III

 
Tout le monde sur ce site

Chapitre III  Halogénation

Partie I

 
Avatar kheira BOUSMAHA
par kheira BOUSMAHA, samedi 9 mai 2020, 22:25
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exercices sur la récursivité

 
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corrigé détaillé de l'exo1 et l'exo2 de la fiche sur la récursivité

 
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Abstract
Feynman–Hibbs corrections in molecular dynamics computer calculations of solid C60 are implemented within the classical effective pair potential approach. The potential model chosen for the site–site interactions is of the Buckingham exp-6 type (Rigby 1986 The Forces Between Molecules (New York: Oxford University Press)), fitted to the Cheng and Klein or the Kitaïgorodsky potential. Structural and thermodynamic properties of the C60 crystal lattice are investigated over a wide range of pressures and temperatures, and data obtained are compared to experimental results and those obtained from a classical approach (Baameur et al 2000 Phys. Status Solidi 220 821). It will be demonstrated that 'quantum corrections' applied in a simple quasi-classical simulations have a great influence upon most calculated properties and increase their accuracy when compared to classical approaches. The observed transition pressure with the distorted lattice and cell contraction compares favourably well with experimental data and equation of state calculations. All measured properties are reported together with the phonon density of states at different pressures.
 
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Abstract
Quantum mechanical studies were carried out in order to understand and describe the nature and strength of the hydrogen bond topology in three dimensional water cluster systems (H2O)n, in the size range 6–20 molecules. Optimal structures and vibrational frequencies of cage like water clusters are computed at the Hartree–Fock (HF) and the electronic density functional theory (DFT) level of theory with a detailed data analysis. Theoretical results are compared to experimental data when available. The general tendency is a decrease of the global minimum energy as the cluster size increases. The nearest neighbour separation between oxygen atoms decreases exponentially when the cluster size increases. The present work suggests that DFT results are in a good agreement with the corresponding HF data, however slight differences remain with regard to values of the nearest neighbour separation between oxygen atoms. The Morokuma’s decomposition of the total interaction energy performed on two and three-dimensional clusters lead to a better understanding of the cluster formation with a strong polarization energy component.
 
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Abstract
The properties of the regular and irregular dodecahedron water clusters (H2O)20, with and without the presence of guest molecules such as N2, CO2, CH4, and C2H6 are calculated at the Hartree–Fock (HF) level of theory with 6-31G(d) basis set. Although the dodecahedron in its regular arrangement is more favourable than the irregular one, embedding a guest molecule in the cavity of the cage structure leads to a different behaviour as far as the calculated data between these two different conformations are concerned. The computed stabilisation energy for each system increases with the presence of the guest molecules in the cavity. The Morokuma’s decomposition of the total interaction energy performed on three dimensional clusters leads to a better understanding of the cluster formation with a strong charge transfer energy component from the host to the guest.