abstract: electrical sensitivity of a beryllium oxide nanotube (beont) was examined toward (c5h5n) molecule by using density functional theory (dft) calculations at the b3lyp/6-31(d) level, and it was found that the adsorption energy (ead) of pyridine on the pristine nanotubes is   a bout -73.29kcal/mol. but when nanotubes has been doped with s and p atomes , the adsorption energy changed . cal...

the relative stability of hydrogen-bonded of molybdate-phosphonic acid (mpa) complex (1:2) ingas phase has been carried out using density functional theory (dft) methods. the methods are usedfor calculations are b3lyp, bp86 and b3pw91 that have been studied in two series of basis sets: d95**and 6-31+g(d,p) for hydrogen and oxygen atoms; lanl2dz for mo and phosphorus. predictedhydrogen-bond geom...

We discuss the basic concepts of density functional theory (DFT) as applied to materials modeling in the microscopic, mesoscopic and macroscopic length scales. The picture that emerges is that of a single unified framework for the study of both quantum and classical systems. While for quantum DFT, the central equation is a one-particle Schrodinger-like Kohn-Sham equation, the classical DFT cons...

objective(s): vinblastine is antimitotic, anticancer medicine that disturbs normal microtubule formation and favours depolymerisation. structural study and finding the active site of vinblastine are the targets of this research.   materials and methods: vinblastine was optimized in vacuum and then in different solvents by density functional theory (dft) method. nuclear magnetic resonance (nmr) ...

in this study, we present the work on the physicochemical interaction between the anti-cancer alkaloidberberine (brb) and dna with the purpose of designing drugs that interact more with dna. molecularmodeling on the complex formed between berberine and dna presented that this complex was undeniablyfully able of participating in the formation of a stable intercalation site. besides, the molecula...

in this research, we report the results of dft calculations using xc-hybrid functional, b3lyp and employ nbo interpretation to investigate the stereoelectronic effects. electrostatic and steric impacts on the conformational properties of 1,2-difluorodiazene (1), 1,2-dichlorodiazene (2) and 1,2-dibromodiazene (3) are also studied. factors determining the thermodynamically stable molecular struct...

In this century, the main concerns of theoretical chemistry obviously make the transition from accurate investigations of small molecules to the designs of complicated large molecular systems; e.g. proteins, nano-materials, environmental catalyses, and so forth. What is necessary for approaching these systems is an accurate theory of low computational order. Density Functional Theory (DFT),, is...

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 o...

despite its numerous potential applications, two-dimensional monolayer graphyne, a novel form of carbon allotropes with sp and sp2 carbon atoms, has received little attention so far, perhaps as a result of its unknown properties. especially, determination of the exact values of its elastic properties can pave the way for future studies on this nanostructure. hence, this article describes a dens...

Nowadays the state of the art Density Functional Theory (DFT) codes are based on local (LDA) or semilocal (GGA) energy functionals. Recently the theory of a truly nonlocal energy functional has been developed. It has been used mostly as a post DFT calculation approach, i.e. by applying the functional on the charge density calculated using any standard DFT code, thus obtaining a new improved val...