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Following recent experimental works, herein we investigated chemical functionalization of a BN graphene-like sheet with hydrazine (N2H4) molecule based on the density functional theory. We found that the functionalization of the pristine sheet is not possible; while the presence of some structural defects such as Stone–Wales is essential to make it feasible. Functionalization energy of the defected sheet is calculated to be in the range of ?6.1 to ?7.4 kcal/mol at B3LYP/6-31G (d) level. Based on the obtained results, the functionalized BN sheet is found to be more soluble in water in comparison with the pristine sheet which is in good agreement with previous experimental reports. Also, it was found that the electronic properties of the defected sheet are slightly changed upon the chemical functionalization. 相似文献
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Ali Ahmadi Peyghan Mohammad Bigdeli Tabar Sirous Yourdkhani 《Journal of Cluster Science》2013,24(4):1011-1020
By using density functional theory calculations, we have investigated the adsorption of OH and OCH3 free radicals on a BC2N nanotube based on the energetic, electronic and geometric properties. The adsorption of radicals on the top of a B atom is more favorable than that on the other sites and reaction energies have been calculated to be in the range of ?0.57 to ?1.48 eV for OH and ?0.27 to ?1.19 eV for OCH3. It was found that the adsorption of radicals may facilitate the electron emission from the BC2N nanotube surface by decreasing the work function due to the charge transfer which occurs between the tube and radicals. Also, HOMO/LUMO gap of the tube is significantly decreased, which may result in the increase of the electrical conductivity of the tube. 相似文献
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Masoumeh Ighaei Bonab Jaber Jahanbin Sardroodi Alireza Rastkar Ebrahimzadeh Faramarz Mehrnejad 《Journal of the Iranian Chemical Society》2017,14(2):357-364
Structural modification of curcumin represents a strategy to improve its stability, water solubility, pharmaceutical properties and bioactivity. In this context, numerous structural analogues of curcumin, including curcuminoids, have been developed. In this paper, the precise density functional theory computations were used for investigating the electronic and geometrical structure of curcumin and some of its derivatives. The chemical activity of the considered molecules was investigated with the help of the global softness and hardness concepts. Among the studied molecules, bisdemethoxycurcumin had the most chemical activity and hexahydrocurcumin had the most stable structure. Among two isomers of the curcumin, the enol isomer was found to be active. 相似文献
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