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901.
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904.
We propose a general scheme for the computational design of new materials using density functional theory. We then apply the scheme to two classes of materials; ferromagnetic ferroelectrics and half-metallic antiferromagnets. Our first “designer” ferromagnetic ferroelectric has subsequently been synthesized and the predicted properties verified. Our computations on half-metallic antiferromagnets have stimulated experimental study but the phenomenon remains unconfirmed. 相似文献
905.
Mattea Carmen Castrovilli Paola Bolognesi Antonella Cartoni Daniele Catone Patrick O’Keeffe Anna Rita Casavola Stefano Turchini Nicola Zema Lorenzo Avaldi 《Journal of the American Society for Mass Spectrometry》2014,25(3):351-367
In the present work, we studied the photoinduced ion chemistry of the halogenated pyrimidines, a class of prototype radiosensitizing molecules, in the energy region 9–15 eV. The work was stimulated by previous studies on inner shell site-selective fragmentation of the pyrimidine molecule, which have shown that the fragmentation is governed by the population/formation of specific ionic states with a hole in valence orbitals, which in turn correlate to accessible dissociation limits. The combined experimental and theoretical study of the appearance energies of the main fragments provides information on the geometric structure of the products and on the role played by the specific halogen atom and the site of halogenation in the dissociation process. This information can be used to gain new insights on the elementary mechanisms that could possibly explain the enhanced radiation damage to the DNA bases or to the medium in which the bases are embedded, thereby contributing to their radiosensitizing effect. Figure
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906.
1,3-Oxazolindin-2-one derivatives were obtained for the first time through carboxylative cyclization of allylamines in the absence of any metal or base catalyst. An electron-withdrawing substituent on the allylic double bond is crucial for the reaction success. Allylamines react with CO2 in MeCN/MeOH mixture and in scCO2 giving satisfactory results. 相似文献
907.
Cover Picture: Combining Topological and Steric Constraints for the Preparation of Heteroleptic Copper(I) Complexes (Chem. Eur. J. 38/2014) 下载免费PDF全文
908.
By using density functional theory calculations at the PBE+U level, we investigated the properties of hematite (0001) surfaces decorated with adatoms/vacancies/substituents. For the most stable surface termination over a large range of oxygen chemical potentials (${\mu _{\rm{O}} }$ ), the vacancy formation and adsorption energies were determined as a function of ${\mu _{\rm{O}} }$ . Under oxygen‐rich conditions, all defects are metastable with respect to the ideal surface. Under oxygen‐poor conditions, O vacancies and Fe adatoms become stable. Under ambient conditions, all defects are metastable; in the bulk, O vacancies form more easily than Fe vacancies, whereas at the surface the opposite is true. All defects, that is, O and Fe vacancies, Fe and Al adatoms, and Al substituents, induce important modifications to the geometry of the surface in their vicinity. Dissociative adsorption of molecular oxygen is likely to be exothermic on surfaces with Fe/Al adatoms or O vacancies. 相似文献
909.
Arcozzi Nicola Monguzzi Alessandro Peloso Marco M. Salvatori Maura 《Journal of Fourier Analysis and Applications》2019,25(4):1958-1986
Journal of Fourier Analysis and Applications - In this paper we study spaces of holomorphic functions on the Siegel upper half-space $${\mathcal U}$$ and prove Paley–Wiener type theorems for... 相似文献
910.
An exploration of the role of para-substituents on the balance between stability and reactivity of N-phenyl trifluoroacetimidates prompted the discovery of new reagents for the addition of allyl and benzyl protecting groups, namely O-allyl and O-benzyl N-(p-nitrophenyl)trifluoroimidates. These compounds are stable and crystalline at ambient temperature, making them ideal alternatives to existing benzylating and allylating reagents used under acidic conditions. 相似文献