The essential oil from the dried leaves of Chromolaena odorata (L.) R.M. King & H. Rob. was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The major components were α-pinene (42.2%), β-pinene (10.6%), germacrene D (9.7%), β-copaen-4α-ol (9.4%), (E)caryophyllene (5.4%), and geijerene/pregeijerene (7.5%). The oil was screened for antimicrobial activity...

Using Hartree–Fock (HF) and ِِDensity Functional Theory (DFT) calculations the thermodynamic properties such as thermal energy , , thermal enthalpy , , thermal entropy , , thermal Gibbs free energy , , heat capacity ,Cv, and molecular structures of several species involving in keto↔enol tautomerism related to acetaldehyde (A), 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and  acetylacetone (AA) h...

For better understanding of conformational stability of the dipeptide model HCO—Gly—L—Leu—NH2,ab initio and DFT computations at HF/6-31G(4 6-311++G(d,p) and B3LYP/6-31G(d) levels oftheory were carried out. Geometry optimization of the dipeptide within the leucine (Leu) side chainangles (x2 ,x2) resulted in three stable conformations as followings: anti-anti, the most stable one,(Xi = 180°, x2 =...

Clonidine has two aromatic rings in which halogens are attached to one ring in this study, both in drug state and in fullerene nanostructure, and by changing the type of halogen at the * HF / 6-31G level and in The gas phase was first optimized and then the NBO calculations were performed. The results obtained in N61, N63 and N5, N3 indicate the highest rhizanese energy and load transfer that, ...

In this paper we have focused on the dielectric constant effect between various solvents with theoretical modelin the biochemical process. Thereby, AAA, UUU, AAG and UUC triplex sequences have been optimized inwater, methanol, ethanol and DMSO with proposed SCRF Model of theory. The solvation of biomolecules isimportant in molecular biology since numerous processes involve to interacting a prot...

A computational study of the electronic structure and stability of complexes formed between Zeolite Y and boric acid was carried out at the HF and B3LYP levels using 6-31G* basis set. Five structures located as local minimum in PES of complex (structures d, e, f, g, and h). The most stable structure is formed due to hydrogen bonding between two hydroxyl of boric acid and both oxygen of ...

Ab initio HF/6-31G* Methode was employed to calculate the bond length in 2- phosphinanes when electronegative groups was at C-2 tend axial and equatorial positions. The magnitude of the anomeric effect depends on the nature of the substituent, the effect of the substituent can be seen by comparing the bond length in 2-chloro and 2- boromo substituented phosphinanes. The effect of anomeric effec...