The Experts below are selected from a list of 37104 Experts worldwide ranked by ideXlab platform
Yury Mishin - One of the best experts on this subject based on the ideXlab platform.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride.
arXiv: Materials Science, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:Tetradymite-Structured chalcogenides such as bismuth telluride Bi_{2}Te_{3} are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_{2}Te_{3}, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride
Nature Communications, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:The atomic level Core Structure of dislocations in non-metallic materials such as chalcogenides remains elusive. Here, the authors combine atomic-resolution electron microscopy and simulations to image a dislocation Core in bismuth telluride and show it spreads because of weak bonding between atomic layers.AbstractTetradymite-Structured chalcogenides such as bismuth telluride (Bi_2Te_3) are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_2Te_3, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
Douglas L. Medlin - One of the best experts on this subject based on the ideXlab platform.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride.
arXiv: Materials Science, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:Tetradymite-Structured chalcogenides such as bismuth telluride Bi_{2}Te_{3} are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_{2}Te_{3}, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride
Nature Communications, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:The atomic level Core Structure of dislocations in non-metallic materials such as chalcogenides remains elusive. Here, the authors combine atomic-resolution electron microscopy and simulations to image a dislocation Core in bismuth telluride and show it spreads because of weak bonding between atomic layers.AbstractTetradymite-Structured chalcogenides such as bismuth telluride (Bi_2Te_3) are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_2Te_3, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
Martin E. Maier - One of the best experts on this subject based on the ideXlab platform.
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Approach to the Core Structure of the Polycyclic Alkaloid Palhinine A
Synlett, 2013Co-Authors: Dominik Gaugele, Martin E. MaierAbstract:A synthesis of the tricyclic partly substituted Core Structure of palhinine A was achieved. To reach the bicyclo[2.2.2]octane motif a domino Michael reaction was employed as a key step. After Arndt–Eistert homologation and intramolecular aldol reaction the isotwistane Core could be obtained after simple functional-group manipulations.
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An approach to the Core Structure of leiodermatolide.
Organic Letters, 2011Co-Authors: Christian Rink, Vaidotas Navickas, Martin E. MaierAbstract:The synthesis of the 16-membered Core Structure of leiodermatolide 40 has been achieved in 26 linear steps starting from (R)-Roche ester. The key steps in the synthesis of 40 are a Stille cross-coupling between two main fragments 11 and 33 having roughly equal size. For the trisubstituted C4/C5 double bond a carbometalation reaction followed by a Suzuki coupling was used. A Yamaguchi macrolactonization furnished macrolactone 39.
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Synthesis of the Core Structure of Cruentaren A
Organic Letters, 2007Co-Authors: Viktor V. Vintonyak, Martin E. MaierAbstract:The Core Structure of the macrolactone cruentaren A (1) was prepared via a ring-closing alkyne metathesis reaction. The corresponding ester 33 was constructed from the benzoic acid derivative 14 and the diol 30. As a key step in the synthesis of acid 14, an aldol reaction resulted in the required anti-OH/Me pattern. The anti-configuration in the stereotetrad of diol 30 was established by a Marshall reaction.
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Concise strategy to the Core Structure of the macrolide queenslandon.
Organic Letters, 2006Co-Authors: Anton S. Khartulyari, Manmohan Kapur, Martin E. MaierAbstract:The fully functionalized Core Structure of the macrolactone queenslandon was prepared using a novel strategy consisting of a glycolate aldol reaction and hydroboration of the derived enol ether 17 followed by Suzuki cross-coupling with an iodostyrene. After conversion of the cross-coupling product to the seco acid 22, Mitsunobu macrolactonization and protecting group manipulations led to the queenslandon model 5.
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Synthesis of the fully functionalized Core Structure of the antibiotic abyssomicin C.
Organic Letters, 2005Co-Authors: Jean-philippe Rath, And Stephan Kinast, Martin E. MaierAbstract:The fully functionalized Core Structure 23 of abyssomicin C (6) containing an oxabicyclooctane ring and a tetronate was prepared via a Diels−Alder approach. After hydroxylation of lactone 10 to the α-hydroxylactone 12, lactone opening led to the hydroxy ester 16. A directed epoxidation furnished the desired syn-epoxide 20. Acetylation of the tertiary hydroxyl group, followed by intramolecular Claisen condensation, gave directly the Core Structure 23.
N. Yang - One of the best experts on this subject based on the ideXlab platform.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride.
arXiv: Materials Science, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:Tetradymite-Structured chalcogenides such as bismuth telluride Bi_{2}Te_{3} are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_{2}Te_{3}, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride
Nature Communications, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:The atomic level Core Structure of dislocations in non-metallic materials such as chalcogenides remains elusive. Here, the authors combine atomic-resolution electron microscopy and simulations to image a dislocation Core in bismuth telluride and show it spreads because of weak bonding between atomic layers.AbstractTetradymite-Structured chalcogenides such as bismuth telluride (Bi_2Te_3) are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_2Te_3, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
Catalin D. Spataru - One of the best experts on this subject based on the ideXlab platform.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride.
arXiv: Materials Science, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:Tetradymite-Structured chalcogenides such as bismuth telluride Bi_{2}Te_{3} are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_{2}Te_{3}, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
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Unraveling the dislocation Core Structure at a van der Waals gap in bismuth telluride
Nature Communications, 2019Co-Authors: Douglas L. Medlin, N. Yang, Catalin D. Spataru, L. M. Hale, Yury MishinAbstract:The atomic level Core Structure of dislocations in non-metallic materials such as chalcogenides remains elusive. Here, the authors combine atomic-resolution electron microscopy and simulations to image a dislocation Core in bismuth telluride and show it spreads because of weak bonding between atomic layers.AbstractTetradymite-Structured chalcogenides such as bismuth telluride (Bi_2Te_3) are of significant interest for thermoelectric energy conversion and as topological insulators. Dislocations play a critical role during synthesis and processing of such materials and can strongly affect their functional properties. The dislocations between quintuple layers present special interest since their Core Structure is controlled by the van der Waals interactions between the layers. In this work, using atomic-resolution electron microscopy, we resolve the basal dislocation Core Structure in Bi_2Te_3, quantifying the disregistry of the atomic planes across the Core. We show that, despite the existence of a stable stacking fault in the basal plane gamma surface, the dislocation Core spreading is mainly due to the weak bonding between the layers, which leads to a small energy penalty for layer sliding parallel to the van der Waals gap. Calculations within a semidiscrete variational Peierls-Nabarro model informed by first-principles calculations support our experimental findings.
