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Gyorgy Keglevich - One of the best experts on this subject based on the ideXlab platform.
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synthesis of 1 amino 2 5 dihydro 1h phosphole 1 Oxides and their n phosphinoyl derivatives bis 2 5 dihydro 1h phosphol 1 yl amine p p diOxides
Synthesis, 2012Co-Authors: Nora Zsuzsa Kiss, Andras Simon, Laszlo Drahos, Krzysztof Huben, Stefan Jankowski, Gyorgy KeglevichAbstract:Depending on the molar ratio of the reactants and on the order of mixing, the reactions of a series of primary amines with 1-chloro-2,5-dihydro-1H-phosphole 1-Oxides prepared in situ from the corresponding hydroxy-dihydrophosphole Oxides afforded 1-amino-2,5-dihydro-1H-phosphole 1-Oxides, or their N-phosphinoyl derivatives, bis(2,5-dihydro-1H-phosphol-1-yl)amine P,P′-diOxides. The latter family of P-heterocycles could also be synthesized by the reaction of 1-amino-2,5-dihydro-1H-phosphole Oxides with chloro-dihydrophosphole Oxides.
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the synthesis of six membered p heterocycles with sterically demanding substituent on the phosphorus atom
Heteroatom Chemistry, 2001Co-Authors: Gyorgy Keglevich, Henrietta Forintos, Melinda Sipos, Andras Dobo, Krisztina Ludanyi, Karoly Vekey, Antal TunglerAbstract:The ring enlargement of 1-(2,4,6-trialkylphenyl)2,5-dihydro-1H-phosphole Oxides (1) via 6,6-dichloro-3-Phosphabicyclo[3.1.0]hexanes (2) afforded the double-bond isomers of 1,2-dihydrophosphinine Oxides (3). Catalytic hydrogenation of the isomeric 1-(di-tert-butyltolyl)-1,2-dihydrophosphinine Oxides (3a) gave the diastereomers of phosphinane oxide (4), while that of the 1-(tri-isopropylphenyl) isomers (5) led predominantly to phospholane Oxides (6) formed by ring contraction. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:528–533, 2001
Geoffroy Hautier - One of the best experts on this subject based on the ideXlab platform.
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structural design principles for low hole effective mass s orbital based p type Oxides
Journal of Materials Chemistry C, 2017Co-Authors: Francesco Ricci, Gianmarco Rignanese, Geoffroy HautierAbstract:High mobility p-type transparent conducting Oxides (TCOs) are critical to current and future optoelectronic devices such as displays, transparent transistors or solar cells. Typical Oxides have flat oxygen-based valence bands leading to high hole effective masses and low mobilities. This makes the discovery of high hole mobility Oxides very challenging. Sn2+ Oxides are known to form Sn-s/O-p mixtures and dispersive valence bands (low hole effective mass). However, not all Sn2+ Oxides exhibit low hole effective mass, pointing to the importance of structural factors. Here, we analyze the electronic structure and chemical bonding of three Sn2+ Oxides of interest as p-type Oxides: SnO and the two K2Sn2O3 polymorphs. We rationalize the differences in their hole effective masses by their Sn–O–Sn angles. As band dispersion is governed by the orbital overlap, Sn–O–Sn angles near 180° maximize the overlap and minimize the hole effective mass. We show that this principle is generalizable to a larger set of Sn2+ Oxides. Our work leads to simple structural design principles for the development of low hole effective mass Oxides based on Sn2+ (but also other reduced main group cations) offering a new avenue for the ongoing search for high mobility p-type TCOs.
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how does chemistry influence electron effective mass in Oxides a high throughput computational analysis
Chemistry of Materials, 2014Co-Authors: Geoffroy Hautier, Anna Miglio, David Waroquiers, Gianmarco Rignanese, Xavier GonzeAbstract:Many technologies require Oxides with high electronic conductivity or mobility (e.g., transparent conducting Oxides, oxide photovoltaics, or photocatalysis). Using high-throughput ab initio computing, we screen more than 4000 binary and ternary Oxides to identify the compounds with the lowest electron effective mass. We identify 74 promising Oxides and suggest a few novel potential n-type transparent conducting Oxides combining a large band gap to a low effective mass. Our analysis indicates that it is unlikely to find Oxides with electron effective masses significantly lower than the current high-mobility binary Oxides (e.g., ZnO and In2O3). Using the large data set, we extract chemical rules leading to low electron effective masses in Oxides. Main group elements with (n–1)d10ns0np0 cations in the rows 4 and 5 and groups 12–15 of the periodic table (i.e., Zn2+, Ga3+, Ge4+, Cd2+, In3+, Sn4+, and Sb5+) induce the lowest electron effective masses because of their s orbitals hybridizing adequately with oxyge...
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identification and design principles of low hole effective mass p type transparent conducting Oxides
Nature Communications, 2013Co-Authors: Geoffroy Hautier, Anna Miglio, Gianmarco Rignanese, Gerbrand Ceder, Xavier GonzeAbstract:The development of high-performance transparent conducting Oxides is critical to many technologies from transparent electronics to solar cells. Whereas n-type transparent con- ducting Oxides are present in many devices, their p-type counterparts are not largely com- mercialized, as they exhibit much lower carrier mobilities due to the large hole effective masses of most Oxides. Here we conduct a high-throughput computational search on thousands of binary and ternary Oxides and identify several highly promising compounds displaying exceptionally low hole effective masses (up to an order of magnitude lower than state-of-the-art p-type transparent conducting Oxides), as well as wide band gaps. In addition to the discovery of specific compounds, the chemical rationalization of our findings opens new directions, beyond current Cu-based chemistries, for the design and development of future p-type transparent conducting Oxides.
Nora Zsuzsa Kiss - One of the best experts on this subject based on the ideXlab platform.
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synthesis of 1 amino 2 5 dihydro 1h phosphole 1 Oxides and their n phosphinoyl derivatives bis 2 5 dihydro 1h phosphol 1 yl amine p p diOxides
Synthesis, 2012Co-Authors: Nora Zsuzsa Kiss, Andras Simon, Laszlo Drahos, Krzysztof Huben, Stefan Jankowski, Gyorgy KeglevichAbstract:Depending on the molar ratio of the reactants and on the order of mixing, the reactions of a series of primary amines with 1-chloro-2,5-dihydro-1H-phosphole 1-Oxides prepared in situ from the corresponding hydroxy-dihydrophosphole Oxides afforded 1-amino-2,5-dihydro-1H-phosphole 1-Oxides, or their N-phosphinoyl derivatives, bis(2,5-dihydro-1H-phosphol-1-yl)amine P,P′-diOxides. The latter family of P-heterocycles could also be synthesized by the reaction of 1-amino-2,5-dihydro-1H-phosphole Oxides with chloro-dihydrophosphole Oxides.
Kyungshik Oh - One of the best experts on this subject based on the ideXlab platform.
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effects of acicular ferrite on charpy impact properties in heat affected zones of oxide containing api x80 linepipe steels
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2011Co-Authors: Hyokyung Sung, Sang Yong Shin, Kyungshik OhAbstract:Abstract This study was concerned with effects of acicular ferrite on Charpy impact properties in heat affected zones (HAZs) of two API X80 linepipe steels containing Oxides. In the one steel, Mg and O 2 were additionally added to form a larger amount of Oxides than the other steel, which was a conventional X80 steel containing a considerable amount of Al and Ti. Various HAZ microstructures were obtained by conducting HAZ simulation tests under different heat inputs of 35 kJ cm −1 and 60 kJ cm −1 . Oxides present in the API X80 linepipe steels were complex Oxides whose average size was 1–2 μm, and the number of Oxides increased with increasing amount of Mg and O 2 . The volume fraction of acicular ferrite present in the steel HAZs increased with increasing number of Oxides, and decreased with increasing heat input. When the volume fraction of acicular in the HAZ was higher than 20%, Charpy impact energy at −20 °C was higher than 100 J as the ductile fracture mode was dominant. Particularly in the steel HAZs having a larger amount of Oxides, Charpy impact properties were excellent because Oxides worked as nucleation sites of acicular ferrite during welding. Charpy impact properties of the HAZs could be well correlated with the volume fraction of acicular ferrite and number of Oxides under different heat input conditions.
Xavier Gonze - One of the best experts on this subject based on the ideXlab platform.
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how does chemistry influence electron effective mass in Oxides a high throughput computational analysis
Chemistry of Materials, 2014Co-Authors: Geoffroy Hautier, Anna Miglio, David Waroquiers, Gianmarco Rignanese, Xavier GonzeAbstract:Many technologies require Oxides with high electronic conductivity or mobility (e.g., transparent conducting Oxides, oxide photovoltaics, or photocatalysis). Using high-throughput ab initio computing, we screen more than 4000 binary and ternary Oxides to identify the compounds with the lowest electron effective mass. We identify 74 promising Oxides and suggest a few novel potential n-type transparent conducting Oxides combining a large band gap to a low effective mass. Our analysis indicates that it is unlikely to find Oxides with electron effective masses significantly lower than the current high-mobility binary Oxides (e.g., ZnO and In2O3). Using the large data set, we extract chemical rules leading to low electron effective masses in Oxides. Main group elements with (n–1)d10ns0np0 cations in the rows 4 and 5 and groups 12–15 of the periodic table (i.e., Zn2+, Ga3+, Ge4+, Cd2+, In3+, Sn4+, and Sb5+) induce the lowest electron effective masses because of their s orbitals hybridizing adequately with oxyge...
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identification and design principles of low hole effective mass p type transparent conducting Oxides
Nature Communications, 2013Co-Authors: Geoffroy Hautier, Anna Miglio, Gianmarco Rignanese, Gerbrand Ceder, Xavier GonzeAbstract:The development of high-performance transparent conducting Oxides is critical to many technologies from transparent electronics to solar cells. Whereas n-type transparent con- ducting Oxides are present in many devices, their p-type counterparts are not largely com- mercialized, as they exhibit much lower carrier mobilities due to the large hole effective masses of most Oxides. Here we conduct a high-throughput computational search on thousands of binary and ternary Oxides and identify several highly promising compounds displaying exceptionally low hole effective masses (up to an order of magnitude lower than state-of-the-art p-type transparent conducting Oxides), as well as wide band gaps. In addition to the discovery of specific compounds, the chemical rationalization of our findings opens new directions, beyond current Cu-based chemistries, for the design and development of future p-type transparent conducting Oxides.