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991.
S. K. Amini 《Journal of Structural Chemistry》2015,56(7):1334-1341
The unassigned configurations of a toxic metabolite to mammals extracted from Neosartorya fischeri (fischerin) in C19, C20, C21, and C22 are assigned as R, R, R, and S, respectively. In this assignment, the extensive ab initio calculations followed by chemical shift computations are performed. Computed chemical shifts are correlated to experimental ones in order to find the correct configuration shown here. 相似文献
992.
M. Köse G. Ceyhan S. A. Güngör S. Purtaş V. McKee 《Journal of Structural Chemistry》2015,56(7):1353-1359
A pyridine–diimine compound N,N′-[pyridine-2,6-diyldi(E)methylylidene]bis(4-chloroaniline) is synthesised by a Schiff base condensation of 2,6-diformylpyridine with 4-chloroaniline in methanol and characterised by spectroscopic and analytical techniques. The molecular structure of the compound is determined by the single crystal X-ray diffraction study. The compound crystallizes in the monoclinic crystal system, I2/c space group with unit cell parameters a = 7.0843(12) Å, b = 6.1909(11) Å, c = 36.262(6) Å, β = 91.576(3)°, V = 1589.8(5) Å3 and Z = 4. There is an intermolecular hydrogen bonding in the molecule resulting in a 1D hydrogen bonding chain and these hydrogen bonding chains are linked by Cl…HC(aromatic) interactions forming a 2D network. Crystal packing of the compound is determined by Cl…HC and π–π interactions. In the fluorescence emission spectra in CH3CN, DMF, DMSO and EtOH, the compound shows only one emission maximum. 相似文献
993.
Z. G. Aliev A. G. Korepin T. K. Goncharov V. A. Garanin S. M. Aldoshin 《Journal of Structural Chemistry》2015,56(7):1367-1372
The X-ray crystallographic analysis of 1,7-difluoro-1,1,3,5,7,7-hexanitro-3,5-diazaheptane has been carried out. We have also determined its sensitivity to mechanical actions and a set of calculated and experimental data on explosion characteristics. 相似文献
994.
A new dinuclear Fe(III) complex, [Fe(5-MeOL1)(OH)0.86(CH3O)0.14]2?2(CH3OH), [H2-5-MeOL1 = N,N′-bis(5-methoxy-2-hydroxybenzylidene)-2,2-dimethylpropane-1,3-diamine], 1 has been synthesized and characterized by single crystal structure analysis. The structure of 1 consists of two Fe(III) centers with one tetradentate schiff base ligand (N2O2) which are bridged by dihydroxo/dimethoxo groups to yield a Fe2O2 core. Complex 1 exhibits weak antiferromagnetic exchange interaction between Fe(III) ions with J = ?0.21 cm–1. 相似文献
995.
Hetero-dimeric magnetic nanoparticles of the type Au-Fe3O4 have been synthesised from separately prepared, differently shaped (spheres and cubes), monodisperse nanoparticles. This synthesis was achieved by the following steps: (a) Mono-functionalising each type of nanoparticles with aldehyde functional groups through a solid support approach, where nanoparticle decorated silica nanoparticles were fabricated as an intermediate step; (b) Derivatising the functional faces with complementary functionalities (e.g. amines and carboxylic acids); (c) Dimerising the two types of particles via amide bond formation. The resulting hetero-dimers were characterised by high-resolution TEM, Fourier transform IR spectroscopy and other appropriate methods. 相似文献
996.
997.
Monte Carlo simulation of full energy spectrum of electrons emitted from silicon in Auger electron spectroscopy 下载免费PDF全文
N. Cao B. Da Y. Ming S. F. Mao K. Goto Z. J. Ding 《Surface and interface analysis : SIA》2015,47(1):113-119
A Monte Carlo simulation including surface excitation, Auger electron‐ and secondary electron production has been performed to calculate the energy spectrum of electrons emitted from silicon in Auger electron spectroscopy (AES), covering the full energy range from the elastic peak down to the true‐secondary‐electron peak. The work aims to provide a more comprehensive understanding of the experimental AES spectrum by integrating the up‐to‐date knowledge of electron scattering and electronic excitation near the solid surface region. The Monte Carlo simulation model of beam–sample interaction includes the atomic ionization and relaxation for Auger electron production with Casnati's ionization cross section, surface plasmon excitation and bulk plasmon excitation as well as other bulk electronic excitation for inelastic scattering of electrons (including primary electrons, Auger electrons and secondary electrons) through a dielectric functional approach, cascade secondary electron production in electron inelastic scattering events, and electron elastic scattering with use of Mott's cross section. The simulated energy spectrum for Si sample describes very well the experimental AES EN(E) spectrum measured with a cylindrical mirror analyzer for primary energies ranging from 500 eV to 3000 eV. Surface excitation is found to affect strongly the loss peak shape and the intensities of the elastic peak and Auger peak, and weakly the low energy backscattering background, but it has less effect to high energy backscattering background and the Auger electron peak shape. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
998.
Ting‐Zheng Xie Kai Guo Zaihong Guo Wen‐Yang Gao Lukasz Wojtas Guo‐Hong Ning Mingjun Huang Xiaocun Lu Jing‐Yi Li Sheng‐Yun Liao Yu‐Sheng Chen Charles N. Moorefield Mary Jane Saunders Stephen Z. D. Cheng Chrys Wesdemiotis George R. Newkome 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(32):9259-9259
999.
Interaction potential models for bulk Zns,Zns nanoparticle,and Zns nanoparticle‐PMMA from first‐principles 下载免费PDF全文
Sadanandam Namsani Nisanth N. Nair Jayant K. Singh 《Journal of computational chemistry》2015,36(15):1176-1186
An ab initio derived transferable polarizable force‐field has been developed for Zinc sulphide (ZnS) nanoparticle (NP) and ZnS NP‐PMMA nanocomposite. The structure and elastic constants of bulk ZnS using the new force‐field are within a few percent of experimental observables. The new force‐field show remarkable ability to reproduce structures and nucleation energies of nanoclusters (Zn1S1‐Zn12S12) as validated with that of the density functional theory calculations. A qualitative agreement of the radial distribution functions of Zn? O, in a ZnS nanocluster‐PMMA system, obtained using molecular mechanics molecular dynamics (MD) and ab initio MD (AIMD) simulations indicates that the ZnS–PMMA interaction through Zn? O bonding is explained satisfactorily by our force‐field. © 2015 Wiley Periodicals, Inc. 相似文献
1000.
Yury D. Fomin Elena N. Tsiok Valentin N. Ryzhov 《Journal of computational chemistry》2015,36(12):901-906
We present the molecular dynamics study of benzene molecules confined into the single wall carbon nanotube. The local structure and orientational ordering of benzene molecules are investigated. It is found that the molecules mostly group in the middle distance from the axis of the tube to the wall. The molecules located in the vicinity of the wall demonstrate some deviation from planar shape. There is a tilted orientational ordering of the molecules which depends on the location of the molecule. It is shown that the diffusion coefficient of the benzene molecules is very small at the conditions we report here. © 2015 Wiley Periodicals, Inc. 相似文献