The Experts below are selected from a list of 189 Experts worldwide ranked by ideXlab platform
Dao-xin Yao - One of the best experts on this subject based on the ideXlab platform.
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Two-Dimensional Honeycomb Monolayer of Nitrogen Group Elements and the Related Nano-Structure: A First-Principle Study
Scientific reports, 2015Co-Authors: Jason Lee, Weiliang Wang, Wen-chuan Tian, Dao-xin YaoAbstract:Because of its novel physical properties, two-dimensional materials have attracted great attention. From first-principle calculations and vibration frequenceis analysis, we predict a new family of two-dimensional materials based on the idea of octet stability: honeycomb lattices of pnictogens (N, P, As, Sb, Bi). The buckled structures of materials come from the sp3 hybridization. These materials have indirect band gap ranging from 0.43eV to 3.7eV. From the analysis of projected density of states, we argue that the s and p orbitals together are sufficient to describe the electronic structure under tight-binding model, and the tight-binding parameters are obtained by fitting the band structures to first-principle results. Surprisingly large on-site spin-orbit coupling is found for all the pnictogen lattices except Nitrogen. Investigation on the electronic structures of both zigzag and armchair nanoribbons reveals the possible existence of spin-polarized ferromagnetic edge states in some cases, which are rare in one-dimensional systems. These edge states and magnetism may exist under the condition of high vaccum and low temperature. This new family of materials would have promising applications in electronics, optics, sensors, and solar cells.
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Two-dimensional octagon-structure monolayer of Nitrogen Group elements and the related nano-structures
Computational Materials Science, 2015Co-Authors: Yu Zhang, Jason Lee, Weiliang Wang, Dao-xin YaoAbstract:Abstract In the purpose of expanding the family of two-dimensional materials, we predict the existence of two-dimensional octa-structure of Nitrogen Group elements that are composed of squares and octagons in first-principle method based on density functional theory (DFT). From our calculations, electronic structures of all monolayers show that they are semiconductors with indirect (N, P, Bi) and direct (As, Sb) band gaps (0.57–2.61 eV). Nano-ribbons of three different unpassivated edges and their band structures are also investigated. Because of the reconstruction on the edges and dangling bonds, there exist ferromagnetic edge states in P, As, Sb nano-ribbons with different edges, and a Dirac point near π is found in the band structure of one specific N nano-ribbon. These structures may be useful in future applications, such as semiconductor devices, spintronics, hydrogen storage and quantum computation.
Jason Lee - One of the best experts on this subject based on the ideXlab platform.
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Two-Dimensional Honeycomb Monolayer of Nitrogen Group Elements and the Related Nano-Structure: A First-Principle Study
Scientific reports, 2015Co-Authors: Jason Lee, Weiliang Wang, Wen-chuan Tian, Dao-xin YaoAbstract:Because of its novel physical properties, two-dimensional materials have attracted great attention. From first-principle calculations and vibration frequenceis analysis, we predict a new family of two-dimensional materials based on the idea of octet stability: honeycomb lattices of pnictogens (N, P, As, Sb, Bi). The buckled structures of materials come from the sp3 hybridization. These materials have indirect band gap ranging from 0.43eV to 3.7eV. From the analysis of projected density of states, we argue that the s and p orbitals together are sufficient to describe the electronic structure under tight-binding model, and the tight-binding parameters are obtained by fitting the band structures to first-principle results. Surprisingly large on-site spin-orbit coupling is found for all the pnictogen lattices except Nitrogen. Investigation on the electronic structures of both zigzag and armchair nanoribbons reveals the possible existence of spin-polarized ferromagnetic edge states in some cases, which are rare in one-dimensional systems. These edge states and magnetism may exist under the condition of high vaccum and low temperature. This new family of materials would have promising applications in electronics, optics, sensors, and solar cells.
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Two-dimensional octagon-structure monolayer of Nitrogen Group elements and the related nano-structures
Computational Materials Science, 2015Co-Authors: Yu Zhang, Jason Lee, Weiliang Wang, Dao-xin YaoAbstract:Abstract In the purpose of expanding the family of two-dimensional materials, we predict the existence of two-dimensional octa-structure of Nitrogen Group elements that are composed of squares and octagons in first-principle method based on density functional theory (DFT). From our calculations, electronic structures of all monolayers show that they are semiconductors with indirect (N, P, Bi) and direct (As, Sb) band gaps (0.57–2.61 eV). Nano-ribbons of three different unpassivated edges and their band structures are also investigated. Because of the reconstruction on the edges and dangling bonds, there exist ferromagnetic edge states in P, As, Sb nano-ribbons with different edges, and a Dirac point near π is found in the band structure of one specific N nano-ribbon. These structures may be useful in future applications, such as semiconductor devices, spintronics, hydrogen storage and quantum computation.
Weiliang Wang - One of the best experts on this subject based on the ideXlab platform.
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Two-Dimensional Honeycomb Monolayer of Nitrogen Group Elements and the Related Nano-Structure: A First-Principle Study
Scientific reports, 2015Co-Authors: Jason Lee, Weiliang Wang, Wen-chuan Tian, Dao-xin YaoAbstract:Because of its novel physical properties, two-dimensional materials have attracted great attention. From first-principle calculations and vibration frequenceis analysis, we predict a new family of two-dimensional materials based on the idea of octet stability: honeycomb lattices of pnictogens (N, P, As, Sb, Bi). The buckled structures of materials come from the sp3 hybridization. These materials have indirect band gap ranging from 0.43eV to 3.7eV. From the analysis of projected density of states, we argue that the s and p orbitals together are sufficient to describe the electronic structure under tight-binding model, and the tight-binding parameters are obtained by fitting the band structures to first-principle results. Surprisingly large on-site spin-orbit coupling is found for all the pnictogen lattices except Nitrogen. Investigation on the electronic structures of both zigzag and armchair nanoribbons reveals the possible existence of spin-polarized ferromagnetic edge states in some cases, which are rare in one-dimensional systems. These edge states and magnetism may exist under the condition of high vaccum and low temperature. This new family of materials would have promising applications in electronics, optics, sensors, and solar cells.
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Two-dimensional octagon-structure monolayer of Nitrogen Group elements and the related nano-structures
Computational Materials Science, 2015Co-Authors: Yu Zhang, Jason Lee, Weiliang Wang, Dao-xin YaoAbstract:Abstract In the purpose of expanding the family of two-dimensional materials, we predict the existence of two-dimensional octa-structure of Nitrogen Group elements that are composed of squares and octagons in first-principle method based on density functional theory (DFT). From our calculations, electronic structures of all monolayers show that they are semiconductors with indirect (N, P, Bi) and direct (As, Sb) band gaps (0.57–2.61 eV). Nano-ribbons of three different unpassivated edges and their band structures are also investigated. Because of the reconstruction on the edges and dangling bonds, there exist ferromagnetic edge states in P, As, Sb nano-ribbons with different edges, and a Dirac point near π is found in the band structure of one specific N nano-ribbon. These structures may be useful in future applications, such as semiconductor devices, spintronics, hydrogen storage and quantum computation.
Hanmin Huang - One of the best experts on this subject based on the ideXlab platform.
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copper catalyzed oxidative amination of benzoxazoles via c h and c n bond activation a new strategy for using tertiary amines as Nitrogen Group sources
ChemInform, 2011Co-Authors: Shengmei Guo, Bo Qian, Yinjun Xie, Chungu Xia, Hanmin HuangAbstract:The presence of the C—H bond α-to Nitrogen in the tertiary amine is crucial for the reaction to proceed.
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copper catalyzed oxidative amination of benzoxazoles via c h and c n bond activation a new strategy for using tertiary amines as Nitrogen Group sources
Organic Letters, 2011Co-Authors: Shengmei Guo, Bo Qian, Yinjun Xie, Chungu Xia, Hanmin HuangAbstract:An efficient and conceptually new method for oxidative amination of azoles with tertiary amines via copper-catalyzed C−H and C−N bond activation has been developed. This protocol can be performed in the absence of external base and only requires atmospheric oxygen as oxidant. The catalyst system is very simple and efficient, which opens a new way for using tertiary amines as Nitrogen Group sources for C−N bond formation reactions.
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Copper-Catalyzed Oxidative Amination of Benzoxazoles via C−H and C−N Bond Activation: A New Strategy for Using Tertiary Amines as Nitrogen Group Sources
Organic letters, 2010Co-Authors: Shengmei Guo, Bo Qian, Yinjun Xie, Chungu Xia, Hanmin HuangAbstract:An efficient and conceptually new method for oxidative amination of azoles with tertiary amines via copper-catalyzed C−H and C−N bond activation has been developed. This protocol can be performed in the absence of external base and only requires atmospheric oxygen as oxidant. The catalyst system is very simple and efficient, which opens a new way for using tertiary amines as Nitrogen Group sources for C−N bond formation reactions.
Yu Zhang - One of the best experts on this subject based on the ideXlab platform.
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Two-dimensional octagon-structure monolayer of Nitrogen Group elements and the related nano-structures
Computational Materials Science, 2015Co-Authors: Yu Zhang, Jason Lee, Weiliang Wang, Dao-xin YaoAbstract:Abstract In the purpose of expanding the family of two-dimensional materials, we predict the existence of two-dimensional octa-structure of Nitrogen Group elements that are composed of squares and octagons in first-principle method based on density functional theory (DFT). From our calculations, electronic structures of all monolayers show that they are semiconductors with indirect (N, P, Bi) and direct (As, Sb) band gaps (0.57–2.61 eV). Nano-ribbons of three different unpassivated edges and their band structures are also investigated. Because of the reconstruction on the edges and dangling bonds, there exist ferromagnetic edge states in P, As, Sb nano-ribbons with different edges, and a Dirac point near π is found in the band structure of one specific N nano-ribbon. These structures may be useful in future applications, such as semiconductor devices, spintronics, hydrogen storage and quantum computation.