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Articles 1 - 11 of 11
Full-Text Articles in Physical Sciences and Mathematics
Reexamine Structures And Relative Stability Of Medium-Sized Silicon Clusters: Low-Lying Endohedral Fullerene-Like Clusters Si30-Si38, Soohaeng Yoo, Nan Shao, Xiao Cheng Zeng
Reexamine Structures And Relative Stability Of Medium-Sized Silicon Clusters: Low-Lying Endohedral Fullerene-Like Clusters Si30-Si38, Soohaeng Yoo, Nan Shao, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
We report improved results of lowest-lying silicon clusters Si31–Si38. A large population of low-energy clusters are collected from previous searches by several research groups and the binding energies of these clusters are computed using density-functional theory (DFT) methods. Best candidates (isomers with high binding energies) are identified from the screening calculations. Additional constrained search is then performed for the best candidates using the basin-hopping method combined with DFT geometry optimization. The obtained low-lying clusters are classified according to binding energies computed using either the Perdew–Burke–Ernzerhof (PBE) functional or the Becke exchange and Lee–Yang–Parr correlation (BLYP) functional. …
Chemically Decorated Boron-Nitride Nanoribbons, Xiao-Jun Wu, Men-Hao Wu, Xiao Cheng Zeng
Chemically Decorated Boron-Nitride Nanoribbons, Xiao-Jun Wu, Men-Hao Wu, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
Motivated by recent studies of graphenen nanoribbons (GNRs), we explored electronic properties of pure and chemically modified boron nitride nanoribbons (BNNRs) using the density functional theory method. Pure BNNRs with both edges fully saturated by hydrogen are semiconducting with wide band gaps. Values of the band gap depend on the width and the type of edge. The chemical decoration of BNNRs’ edges with four different functional groups, including -F, -Cl, -OH, and -NO2, was investigated. The band-gap modulation by chemical decoration may be exploited for nanoelectronic applications.
Coexistence And Transition Between Cassie And Wenzel State On Pillared Hydrophobic Surface, Takahiro Koishi, Kenji Yasuoka, Shigenori Fujikawa, Toshikazu Ebisuzaki, Xiao Cheng Zeng
Coexistence And Transition Between Cassie And Wenzel State On Pillared Hydrophobic Surface, Takahiro Koishi, Kenji Yasuoka, Shigenori Fujikawa, Toshikazu Ebisuzaki, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
Water droplets on rugged hydrophobic surfaces typically exhibit one of the following two states: (i) the Wenzel state [Wenzel RN (1936) Ind Eng Chem 28:988–994] in which water droplets are in full contact with the rugged surface (referred as the wetted contact) or (ii) the Cassie state [Cassie, ABD, Baxter S (1944) Trans Faraday Soc 40:546–551] in which water droplets are in contact with peaks of the rugged surface as well as the “air pockets” trapped between surface grooves (the composite contact). Here, we show large-scale molecular dynamics simulation of transition between Wenzel state and Cassie state of water droplets …
One-Pot Formation Of Large Macrocycles With Modifiable Peripheries And Internal Cavities, Joseph S. Ferguson, Kazuhiro Yamato, Rui Liu, Lan He, Xiao Cheng Zeng, Bing Gong
One-Pot Formation Of Large Macrocycles With Modifiable Peripheries And Internal Cavities, Joseph S. Ferguson, Kazuhiro Yamato, Rui Liu, Lan He, Xiao Cheng Zeng, Bing Gong
Xiao Cheng Zeng Publications
Macrocycles with persistent shape and large, noncollapsible lumens have attracted increasing interest because of their unique properties and potential applications.[1] Although most of the macrocycles with well-defined shape have hydrocarbon backbones formed from the stepwise coupling of sp- or sp2-hybridized carbon atoms,[1a,b,d, 2] macrocycles with other rigid backbones have also been reported.[3] For example, we discovered a series of aromatic oligoamide macrocycles that could be generated in high yield by a one-pot macrocyclization process.[4] These readily available macrocycles contain hydrophilic cavities that are rich in carbonyl oxygen atoms. With their persistent shape and noncollapsible cavities, these macrocycles have demonstrated unique …
Materials Design Of Half-Metallic Graphene And Graphene Nanoribbons, Menghao Wu, Xiaojun Wu, Yi Gao, Xiao Cheng Zeng
Materials Design Of Half-Metallic Graphene And Graphene Nanoribbons, Menghao Wu, Xiaojun Wu, Yi Gao, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
Through patterned chemical modification, we show that both graphene sheets and zigzag-edged graphene nanoribbons (ZGNRs) can be converted to half-metals as long as the unmodified carbon strip (or width of ZGNRs) is sufficiently wide. Periodically functionalized graphene can mimic electronic behavior of edge-modified ZGNRs as the edge-modified zigzag carbon chains effectively divide a graphene sheet into a series of identical ZGNRs.
First-Principles Study Of Methane Dehydrogenation On A Bimetallic Cu/N(111) Surface, Wei An, Xiao Cheng Zeng, C. Heath Turner
First-Principles Study Of Methane Dehydrogenation On A Bimetallic Cu/N(111) Surface, Wei An, Xiao Cheng Zeng, C. Heath Turner
Xiao Cheng Zeng Publications
We present density-functional theory calculations of the dehydrogenation of methane and CHx (x = 1 – 3) on a Cu/Ni(111) surface, where Cu atoms are substituted on the Ni surface at a coverage of 1/4 monolayer.
Co Chemisorption On The Surfaces Of The Golden Cages, Wei Huang, Satya S. Bulusu, Rhitankar Pal, Xiao Cheng Zeng, Lai-Sheng Wang
Co Chemisorption On The Surfaces Of The Golden Cages, Wei Huang, Satya S. Bulusu, Rhitankar Pal, Xiao Cheng Zeng, Lai-Sheng Wang
Xiao Cheng Zeng Publications
We report a joint experimental and theoretical study of CO chemisorption on the golden cages. We find that the Au17 − cage is highly robust and retains its cage structure in Au17 − (CO)−. On the other hand, the Au16 − cage is transformed to a structure similar to Au17 − upon the adsorption of CO. Au18 − is known to consist of two nearly degenerate structures, i.e., a cage and a pyramidal isomer, which coexist in the cluster beam. However, upon CO chemisorption only the cage isomer is observed while the pyramidal …
Magnetic Doping Of The Golden Cage Cluster M@Au16− (M=Fe,Co,Ni), Lei-Ming Wang, Jaeil Bai, Anne Lechtken, Wei Huang, Detlef Schooss, Manfred Kappes, Xiao Cheng Zeng, Lai-Sheng Wang
Magnetic Doping Of The Golden Cage Cluster M@Au16− (M=Fe,Co,Ni), Lei-Ming Wang, Jaeil Bai, Anne Lechtken, Wei Huang, Detlef Schooss, Manfred Kappes, Xiao Cheng Zeng, Lai-Sheng Wang
Xiao Cheng Zeng Publications
Structural, electronic, and magnetic properties of the golden cage doped with a transition-metal atom, MAu16- (M =Fe,Co,Ni), are investigated using trapped ion electron diffraction, photoelectron spectroscopy, and density-functional theory. The best agreement to experiment is obtained for endohedral M@Au16- structures but with considerable distortions to the parent Au16- cage. Fe@Au16- and Co@Au16- are found to have similar structures with C2 symmetry while a C1 structure is obtained for Ni@Au16-. The 4s electrons are observed to transfer to the Au16 cage, whereas atomiclike …
Tuning The Electronic Properties Of The Golden Buckyball By Endohedral Doping: M@Au16− (M=Ag,Zn, In), Lei-Ming Wang, Rhitankar Pal, Wei Huang, Xiao Cheng Zeng, Lai-Sheng Wang
Tuning The Electronic Properties Of The Golden Buckyball By Endohedral Doping: M@Au16− (M=Ag,Zn, In), Lei-Ming Wang, Rhitankar Pal, Wei Huang, Xiao Cheng Zeng, Lai-Sheng Wang
Xiao Cheng Zeng Publications
The golden Au16- cage is doped systematically with an external atom of different valence electrons: Ag, Zn, and In. The electronic and structural properties of the doped clusters, MAu16- (M =Ag,Zn, In), are investigated by photoelectron spectroscopy and theoretical calculations. It is observed that the characteristic spectral features of 16-, reflecting its near tetrahedral (Td) symmetry, are retained in the photoelectron spectra of MAu16-, suggesting endohedral structures with little distortion from the parent Au16- cage for the doped clusters. Density functional calculations show that …
Dipole-Induced, Thermally Stable Lamellar Structure By Polar Aromatic Silane, Jinyue Jiang, Ocelio V. Lima, Yong Pei, Xiao Cheng Zeng, Li Tan, Eric Forsythe
Dipole-Induced, Thermally Stable Lamellar Structure By Polar Aromatic Silane, Jinyue Jiang, Ocelio V. Lima, Yong Pei, Xiao Cheng Zeng, Li Tan, Eric Forsythe
Xiao Cheng Zeng Publications
Lamellar structures, consisting of alternating inorganic layers separated by organic moieties, have attracted much attention over a wide range of applications, such as polymer-clay composites, rheology control, and optoelectronic devices. Organosilanes are ideal candidates for such efforts due to their ability to self-assemble and the intrinsic hybrid configuration of organic/inorganic moieties. Yet, the main emphasis has been focused on alkylsilane, where an alkyl group is linked with a silane terminal, i.e., R-SiX3 (R is alkane and X can be halogen or alkoxy). Construction of stacked monolayers of alkylsilane through chemisorption is possible. The demonstrated pathway usually takes place after …
On The Phase Diagram Of Water With Density Functional Theory Potentials: The Melting Temperature Of Ice /H With The Perdew–Burke–Ernzerhof And Becke–Lee–Yang–Parr Functionals, Soohaeng Yoo, Xiao Cheng Zeng, Sotiris C. Xantheas
On The Phase Diagram Of Water With Density Functional Theory Potentials: The Melting Temperature Of Ice /H With The Perdew–Burke–Ernzerhof And Becke–Lee–Yang–Parr Functionals, Soohaeng Yoo, Xiao Cheng Zeng, Sotiris C. Xantheas
Xiao Cheng Zeng Publications
The melting temperature (Tm) of ice Ih was determined from constant enthalpy and pressure (NPH) Born–Oppenheimer molecular dynamics simulations to be 417±3 K for the Perdew–Burke– Ernzerhof and 411±4 K for the Becke–Lee–Yang–Parr density functionals using a coexisting ice (Ih)-liquid phase at constant pressures of P=2500 and 10 000 bar and a density p=1 g/cm3, respectively.