scholarly journals SIMULATION OF X-RAY EMISSION AND PHOTOELECTRON SPECTRA OF H2Pc USING THE DENSITY FUNCTIONAL METHOD

2015 ◽  
Vol 56 (3) ◽  
Keyword(s):  
Density Functional ◽  
Density Functional Method ◽  
Functional Method ◽  
Photoelectron Spectra ◽  
X Ray

Simulation of X-ray emission and photoelectron spectra of H2Pc using the density functional method

2015 ◽  
Vol 56 (3) ◽  
pp. 523-530 ◽  
Author(s):  
G. I. Semushkina ◽  
L. N. Mazalov ◽  
S. A. Lavrukhina ◽  
T. V. Basova ◽  
R. V. Gulyaev
Keyword(s):  
Density Functional ◽  
Density Functional Method ◽  
Functional Method ◽  
Photoelectron Spectra ◽  
X Ray

Theoretical and Experimental Studies of Structural Defects in CeO2 Nanoparticles

2020 ◽  
Vol 312 ◽  
pp. 68-73
Author(s):  
Maxim A. Pugachevskii ◽  
Andrey N. Chibisov ◽  
A.P. Kuzmenko ◽  
Aleksandr S. Fedorov
Keyword(s):  
Density Functional ◽  
Oxygen Vacancies ◽  
Cell Parameter ◽  
Density Functional Method ◽  
Experimental Studies ◽  
Functional Method ◽  
Structural Defects ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Energy Loss

The atomic structure and morphology of cerium oxide nanoparticles obtained by laser ablation are experimentally and theoretically investigated. Using transmission electron microscopy, X-ray diffractometry, and electron energy loss spectroscopy, it has been shown that particles are enriched in oxygen vacancies that stabilize their internal structure. The density functional method was used to study the dependence of the unit cell parameter of CeO2 nanoparticles on their size. An analysis of the charge density distribution shows a different structural distribution of Ce3+ and Ce4+ atoms in nanoparticles.

New Ultra High CIS Polybutadiene Through a Novel Neodymium Catalyst

2002 ◽  
Vol 75 (5) ◽  
pp. 907-922 ◽  
Author(s):  
Gwanghoon Kwag ◽  
Aju Kim ◽  
Seunghwon Lee ◽  
Youngchan Jang ◽  
Pillsung Kim ◽  
...  
Keyword(s):  
Density Functional ◽  
Density Functional Method ◽  
Physical And Mechanical Properties ◽  
Functional Method ◽  
Edge Structure ◽  
X Ray ◽  
Butadiene Polymerization ◽  
Monomeric Structure ◽  
Ultra High Cis Polybutadiene ◽  
X Ray Absorption

Abstract A significant improvement in the catalytic activity of Nd-based catalyst for 1,3-butadiene polymerization has been achieved using a novel neodymium compound, NdH(neodecanoate)4 (Nd( neodecanoate)3 (neodecanoic acid)). The neodymium compound was characterized with a matrix assisted laser desorption ionization (MALDI) mass spectroscopy, with a synchrotron X-ray absorption spectroscopy (XAS), and with computer simulations. A distinguished molecular ion peak (m/z=838.7, [M]) and a pronounced absorption edge are observed in the mass and in the Nd-LIII XANES(X-ray absorption near edge structure) spectra of NdH(neodecanoate)4, respectively, which evidence its monomeric structure. An active-center of the monomeric Nd-catalyst is fully optimized by density functional method (B3LYP/CEP-31G), in which neodymium(III) is coordinated with carboxylate, allylic active end, penultimate double bond, and chloride. The bond distances are Nd-C1 2.586 A˚, Nd-C4 2.741 A˚, Nd-C5 2.738 A˚, Nd-Cl 2.651 A˚, and Nd-O1 2.167 A˚, respectively. The Nd-catalyst shows a high activity (1.6×106 g/Nd md·h) and produces polybutadiene with 99% cis content. The ultra high cis polybutadiene produced by the Nd-catalyst exhibits excellent physical and mechanical properties such as high abrasion resistance, rebound, tensile properties and remarkably low heat build-up, which will greatly improve tire performance.

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