Molecular structure

دسترسی آزاد مقاله

1 - Modeling of the hydration shell of Adenine
K. Zare N. Karimi R.l Savadi A. Abedi M.A. Sevedsadiadi

The molecular geometry of complex of adenine with 8 water molecules was calculated with Hartree-Fock (HF). The standard 6-31G(d) basis set has been employed. The existence of C-H…O Hydrogen bonds between the water molecules and the hydrophobic part of nucleobase چکیده کامل

The molecular geometry of complex of adenine with 8 water molecules was calculated with Hartree-Fock (HF). The standard 6-31G(d) basis set has been employed. The existence of C-H…O Hydrogen bonds between the water molecules and the hydrophobic part of nucleobase is stablished. We optimized structures and computed interaction energies of all complexes of adenine with water molecules step by step, and finally compared them. Moreover, a theoretical investigation of the complex of adenine with 8 water molecules has led to the conclusion that the molecular structure of this molecule cannot be described by conventional chemical formula. The result of an AB initio Hartree-fock study of the structural parameters, atomic charge, dipole moment and thermodynamic change for isolated and poly hydrated adenine complexes are reported. Finally the gauge-invariant atomic orbital (GIAO) method was employed to calculate isotropic atomic shielding of complex using HF theory. پرونده مقاله

دسترسی آزاد مقاله

2 - Structural Relationship Between Randić Indices, Adjacency, Distance Matrixes and Molar Absorption Coefficient of Linear Conjugated Polyene Compounds
Avat (Arman) Taherpour Fatemeh Shafiee

One of the useful indices in molecular topology is Randić index. The alternative double bonds andconjugation in the polyene compounds are one of the main properties in these compounds. Someof the molecular orbital and structural properties refer to this specialty, such چکیده کامل

One of the useful indices in molecular topology is Randić index. The alternative double bonds andconjugation in the polyene compounds are one of the main properties in these compounds. Someof the molecular orbital and structural properties refer to this specialty, such as: molar absorptioncoefficient (εmax) , electrical conductivity and difference energy level of the HOMO and LUMOorbitals, etc. Here, the relationship of the structural topologies such as the Randić indices,adjacency and distance matrixes to molar absorption coefficient (εmax) of the linear conjugatedpolyenes was represented. For calculation the εmax of the compounds could use the Fiser-Kuhnrule. The interesting results of concerning amoung εmax and the above indices are presented. پرونده مقاله

دسترسی آزاد مقاله

3 - Topological Relationship Between One-Dimensional Box Model and Randić Indices in Linear Simple Conjugated Polyenes
Avat (Arman) Taherpour Fatemeh Shafiei

The alternative double bonds and conjugation in the polyene compounds are one of the main properties in these compounds. Each carbon-carbon bonds in a polyene compound along the chain has appreciable double-bond character. The p-electrons are therefore not localized but چکیده کامل

The alternative double bonds and conjugation in the polyene compounds are one of the main properties in these compounds. Each carbon-carbon bonds in a polyene compound along the chain has appreciable double-bond character. The p-electrons are therefore not localized but are relatively free to move throughout the entire carbon skeleton as an one-dimensional box. The skeleton be considered as a roughly uniform region of low potential bounded at the ends of the polyene by regions of infinitely high potential. Graph theory provides the useful natural mathematical frameworks for the quantitative codification of classical chemical bonding ideas. One of the useful indices for examination of structure-property relationship is Randić index. Some of properties here considered are associated with the molecular orbital method include and λmax, the difference energy level of the HOMO and LUMO orbitals (ΔE) and the length of the electron moving in carbon skeleton as one-dimensional box in polyene compounds (1-D box model). In this study, the difference of the length of carbon skeleton of polyenes and the length of the electron moving in the carbon skeleton will be discussed. For calculation the λmax of the compounds could use the Fieser-Kuhn rule. The interesting results of concerning among λmax, ΔE, the electron moving in carbon skeleton of simple linear polyenes by the use of 1-D box model and the above indices are presented. پرونده مقاله

دسترسی آزاد مقاله

4 - Application of Graph Theory to Some Thermodynamic Properties and Topological Indices
H. Aghaie M. Monajjemi F. Shafiei

The relationship between the Randic , Wiener, Hosoya , Balaban, Schultz indices, Harary numbers andDistance matrix to enthalpies of formation (Airf), heat capacity, (Cp) , enthalpies of combustion (AH °c ),enthalpy of vaporization (AH °vap) and normal boiling po چکیده کامل

The relationship between the Randic , Wiener, Hosoya , Balaban, Schultz indices, Harary numbers andDistance matrix to enthalpies of formation (Airf), heat capacity, (Cp) , enthalpies of combustion (AH °c ),enthalpy of vaporization (AH °vap) and normal boiling points (bpK)of C2 C10 normal alkanes isrepresented پرونده مقاله

دسترسی آزاد مقاله

5 - Dynamical distance as a semi-metric on nuclear configuration space
M. Rahimi

In this paper, we introduce the concept of dynamical distance on a nuclear configuration space. We partition the nuclear conguration space into disjoint classes. This classification coincides with the classical partitioning of molecular systems via the concept ofconjuga چکیده کامل

In this paper, we introduce the concept of dynamical distance on a nuclear configuration space. We partition the nuclear conguration space into disjoint classes. This classification coincides with the classical partitioning of molecular systems via the concept ofconjugacy of dynamical systems. It gives a quantitative criterion to distinguish differentmolecular structures. پرونده مقاله

فهرست مقالات Molecular structure

سکوی نشر دانش

پیوندهای سایت

مراکز مرتبط

پشتیبانی

صفحات رسمی