In this research DFT/B3LYP method has been employed to investigate the geometrical structures, relative stabilities, and electronic properties of Cun (n=3–10) clusters for clarifying the effect of size on the properties. Through a careful analysis of the successive binding energies, second-order difference of energy and the highest occupied-lowest unoccupied molecular orbital energy gaps as a function of cluster size, an odd-even alternative phenomenon has been observed. The results show that the clusters with even number of copper atoms present relatively higher stabilities.

The Density Functional Theory (DFT) and the Natural Bond Orbital (NBO) calculations based method B3LYP/6-31G* were carried out to study the interaction of carbon nanotube (8, 0) with nitrobenzene in two situations perpendicular and parallel. Formation energies of compounds, charges, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) and the HOMO-LUMO band gap were calculated. The parallel direction is more stable than the perpendicular direction. The lower HOMO-LUMO gaps confirm this stability.

The Density Functional Theory (DFT) and the Natural Bond Orbital (NBO) calculations based method B3LYP/6-31G were carried out to study the interaction of Dopamine with carbon nanotube. The nanotube used in this study, includes 60 C atoms (6, 6) type. Relative and formation energies of compounds, Muliken charges, occupancy, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), the HOMO-LUMO band gap and the electronic chemical potential (m) were calculated. The NBO analysis showed there is a hyperconjugative interaction between Oxygen and Nitrogen lone-pair electrons of dopamine and s* or p* orbitals of carbon atom of nanotube. Results indicated that the composite between nanotubes and the Ncentered dopamine is more stable than O1-centered dopamine and both of them are stable than the single agent.

In this paper, the synthesis of various enaminones from the reaction of 3-aminocoumarin and ethyl-2, 4-dioxo-4-arylbutanoate in the presence of p-toluene sulfonic acid is reported. The reaction was examined under different solvents and catalytic systems, which clearly proved the importance of acidic catalyst in this organic transformation. This work was also accompanied by density functional theory (DFT) studies to justify the formation of final products.

The molecular structure of Cyclophosphamide (‘N, N-bis (2-chloroethyl) -1, 3, 2-oxazaphosphinan-2-amine 2-oxide’ is the anti cancer drug and used to treat cancer and immune diseases) and SWCNTs were calculated by the B3LYP density functional model with 6-311G* basis set with Gaussian 09 program. The nanotube used in this study, includes 120 C atoms (5, 5) type. The NBO analysis showed there is a hyperconjugative interaction between Oxygen lone-pair electrons of Cyclophosphamide and s* οr  p* orbitals of carbon atom of nanotube. Also chemical shift isotropy (s), chemical shift anisotropy (D s) ), asymmetry parameter( h) of this compounds have been reported.

The term electronegativity was introduced by Linus Pauling, who characterized on the basis of thermodynamic data from the energies of the single bonds. In present study, the Density Functional Theory (DFT) was used to calculate electronegativity of atoms. The base of calculation is similar to Pauling and Mulliken methods. The results indicate that the largest value of electronegativity for Fluorine atom and then plotted the electronegativity values versus to atomic numbers. We have selected scale of electronegativity base on Pauling’s method. Also we presented an empirical formula for electronegativity calculation that the value of the electronegativity is a function of number of valence electron, in addition to ionization potential and electron affinity. Our novel strategy designed by Natural Population Analysis (NPA) method. All calculations were performed using B3LYP method and aug-cc-pVTZ, 6-311++G (2df), SDDALL and LANL2DZ basis set in Gaussian 03W.

Introduction: Sugar cane and the sugar produced from this plant contain various phenolic compounds with reasonable antioxidant potential. Therefore the aim of this study is to investigate the possibility of measuring phenolic compounds in brown sugar by DFT method. Materials and Methods: In this research work, sugar in second and third stages of cooking were sampled and by application of high performance liquid chromatography, the quality and the ratio of phenolic compounds were identified and determined. In the second stage, and for the first time, using the advanced computational method, the DFT density theory, based on Bond Desociation Energy (BDE) and Ionization Potential (IP), the antioxidant property of these types of compounds were obtained. For these calculations, particular attention has been paid to thermodynamic properties based on corrected enthalpy energy. Results: The results indicated that by comparing BDE and IP, the identified compounds showed that chenifrol alcohol had the highest and benzoic acid had the least antioxidant activity in both sugar cooking batch(II) and sugar cooking batch(III). Conclusion: Based on the findings, it was concluded that phenolic compounds identified in sugar cooking batch(II) and sugar cooking batch(III), benzoic acid and chenifrol alcohol have the least and the highest antioxidant properties respectively.

In this paper, a new method is proposed to estimate the direction of arrival (DOA) using non-uniform linear array structure and modeling the measurement matrix as a DFT matrix. In order to estimate the DOA using compressive sensing (CS), continuous angle space should be divided into a discrete set using small steps. This division, leads to the increment of mutual coherence between columns of the measurement matrix and performance of the sparse recovery algorithms is degraded. To solve this problem, we propose a new method in which DFT matrix with mutual coherence of zero is used as the measurement matrix. In order to increase the accuracy of estimation, the size of DFT matrix or the number of antennas should be increased. Implementation of an array with large number of antennas is complex and expensive. A solution to decrease the number of antennas is using a non-uniform linear array and constructing a virtual uniform linear array. A virtual uniform linear array can be constructed by vectorizing the correlation matrix of the received signal of a non-uniform linear array. Increasing the number of antennas in the virtual array will increase the size of DFT matrix. Therefore, the accuracy of DOA estimation will be increased. Simulation results show that DOA estimation using compressive sensing, based on DFT measurement matrix, has a good performance in terms of mean square error of estimation.

In this research drugs was investingatcd on different snbstratcs. It is a model of drug named pigmedin which the effect of Nbr effect in drug delivery was investrated. For thvis purpose NBr tube with variouse lengths and nano carbon was investigated. The gussian software and DFT/b31yp method and 3-21 G and 6-31 G series was used for study on the effect of nano structures on the drug nature, piymedil molechle directly connected to every nano structures, from head and calculation completed in 2phase of sas and liquid. The result demens trated that the cannection of drug to nanostructunes due to improv solubility of druy. energy, Angles band length and dipole maman was calculated to choose the best structure.