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Wei Huang

Bio: Wei Huang is an academic researcher from University of Science and Technology of China. The author has contributed to research in topics: Cluster (physics) & Density functional theory. The author has an hindex of 33, co-authored 176 publications receiving 3648 citations. Previous affiliations of Wei Huang include Brown University & Washington State University Tri-Cities.


Papers
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Journal ArticleDOI
TL;DR: An investigation of the B₁₉⁻ cluster is reported, which shows chemical bonding reminiscent of that inannulene andcirculene, which possesses a unique double π-aromaticity in two concentric ρ-systems.
Abstract: A combined theoretical and experimental approach has been used to investigate the structure and bonding of an all-boron cluster (B19−). Calculations suggest that the minimum energy structure is a near-planar one — in which a pentagonal B6 unit is encircled by a larger B13 ring — possessing two concentric aromatic π systems.

447 citations

Journal ArticleDOI
TL;DR: Using the Ar titration and tagging, isomer-specific photoelectron spectra for the 2D and 3D Au12- are obtained and confirm the2D to 3D structural transition at this size.
Abstract: Different physisorption properties by 2D and 3D isomers of Au_{n};{-} clusters are observed and used to probe the 2D to 3D structural transition. Strong Ar clustering occurs on planar Au_{n};{-} and the planar faces of the pyramidal Au20-. An abrupt change of Ar clustering at Au12- confirms the 2D to 3D structural transition at this size, where both isomers coexist. The minor 2D isomer can be titrated out by Ar to produce a clean 3D-Au12- beam and beams of Au_{12}Ar_{m};{-} with enhanced 2D isomers. Using the Ar titration and tagging, isomer-specific photoelectron spectra for the 2D and 3D Au12- are obtained.

154 citations

Journal ArticleDOI
TL;DR: The structures and bonding of CB6-, C2B5-, and CB62- are investigated by photoelectron spectroscopy and ab initio calculations and it is shown that the global minimum structures for these systems are distorted heptacyclic structures.
Abstract: In the past two decades, computational chemistry has made dramatic advances, enabling the prediction of novel molecules that often contradict chemical intuition. Many theoretical chemists have participated in this endeavor, proposing myriads of unusual molecules. However, very often the predicted species are not the global minima, and it is difficult if not impossible to observe them experimentally. Molecules with hypercoordinated carbons in planar boron-carbon clusters are vivid examples of such predictions. Here we aim to show via a joint experimental and theoretical investigation that such species are too high in energy to be experimentally observed.

151 citations

Journal ArticleDOI
01 May 2008-ACS Nano
TL;DR: In this article, photoelectron spectroscopy of size-selected anions, in combination with first principles calculations, was used to elucidate the structures of gold nanoclusters in a critical size regime from 55 to 64 atoms (1.1−1.3 nm in diameter).
Abstract: The atomic structures of bare gold clusters provide the foundation to understand the enhanced catalytic properties of supported gold nanoparticles. However, the richness of diverse structures and the strong relativistic effects have posed considerable challenges for a systematic understanding of gold clusters with more than 20 atoms. We use photoelectron spectroscopy of size-selected anions, in combination with first principles calculations, to elucidate the structures of gold nanoclusters in a critical size regime from 55 to 64 atoms (1.1−1.3 nm in diameter). Au55− is found to be a nonicosahedral disordered cluster as a result of relativistic effects that induce strong surface contractions analogous to bulk surface reconstructions, whereas low-symmetry core−shell-type structures are found for Au56− to Au64−. Au58 exhibits a major electron-shell closing and is shown to possess a low-symmetry, but nearly spherical structure with a large energy gap. Clear spectroscopic and computational evidence has been ob...

123 citations

Journal ArticleDOI
TL;DR: A systematic investigation of the interactions between O(2) and small gold cluster anions Au(n)(-) (n = 1-7) using photoelectron spectroscopy provides further insight into O( 2) interactions with small gold clusters, as well as accurate experimental data to benchmark theoretical investigations.
Abstract: Activation of O2 is the most critical step in catalytic oxidation reactions involving gold and remains poorly understood. Here we report a systematic investigation of the interactions between O2 and small gold cluster anions Aun− (n = 1−7) using photoelectron spectroscopy. Higher resolution photoelectron spectra are obtained for the molecularly chemisorbed even-sized AunO2− (n = 2, 4, 6) complexes. Well-resolved vibrational structures due to O−O stretching are observed and can be readily distinguished from the Au-derived PES bands. The adiabatic detachment energies and O−O vibrational frequencies are measured to be 3.03 ± 0.04, 3.53 ± 0.05, and 3.17 ± 0.05 eV, and 1360 ± 80, 1360 ± 80, and 1330 ± 80 cm−1 for n = 2, 4, 6, respectively. Physisorbed Aun−(O2) complexes for n = 1, 3, 5, 7 are observed for the first time, providing direct evidence for the inertness of the closed-shell odd-sized Aun− clusters toward O2. Neutral even-sized Aun clusters are closed-shell and are expected to be inert toward O2, whic...

118 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal Article
TL;DR: In this article, a fast Fourier transform method of topography and interferometry is proposed to discriminate between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour generation techniques.
Abstract: A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

3,742 citations

Journal Article
TL;DR: In this paper, an inventory of air pollutant emissions in Asia in the year 2000 is developed to support atmospheric modeling and analysis of observations taken during the TRACE-P experiment funded by the National Aeronautics and Space Administration (NASA) and the ACE-Asia experiment, in which emissions are estimated for all major anthropogenic sources, including biomass burning, in 64 regions of Asia.
Abstract: [i] An inventory of air pollutant emissions in Asia in the year 2000 is developed to support atmospheric modeling and analysis of observations taken during the TRACE-P experiment funded by the National Aeronautics and Space Administration (NASA) and the ACE-Asia experiment funded by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA). Emissions are estimated for all major anthropogenic sources, including biomass burning, in 64 regions of Asia. We estimate total Asian emissions as follows: 34.3 Tg SO 2 , 26.8 Tg NO x , 9870 Tg CO 2 , 279 Tg CO, 107 Tg CH 4 , 52.2 Tg NMVOC, 2.54 Tg black carbon (BC), 10.4 Tg organic carbon (OC), and 27.5 Tg NH 3 . In addition, NMVOC are speciated into 19 subcategories according to functional groups and reactivity. Thus we are able to identify the major source regions and types for many of the significant gaseous and particle emissions that influence pollutant concentrations in the vicinity of the TRACE-P and ACE-Asia field measurements. Emissions in China dominate the signature of pollutant concentrations in this region, so special emphasis has been placed on the development of emission estimates for China. China's emissions are determined to be as follows: 20.4 Tg SO 2 , 11.4 Tg NO x , 3820 Tg CO 2 , 116 Tg CO, 38.4 Tg CH 4 , 17.4 Tg NMVOC, 1.05 Tg BC, 3.4 Tg OC, and 13.6 Tg NH 3 . Emissions are gridded at a variety of spatial resolutions from 1° × 1° to 30 s x 30 s, using the exact locations of large point sources and surrogate GIS distributions of urban and rural population, road networks, landcover, ship lanes, etc. The gridded emission estimates have been used as inputs to atmospheric simulation models and have proven to be generally robust in comparison with field observations, though there is reason to think that emissions of CO and possibly BC may be underestimated. Monthly emission estimates for China are developed for each species to aid TRACE-P and ACE-Asia data interpretation. During the observation period of March/ April, emissions are roughly at their average values (one twelfth of annual). Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of ±16% for SO 2 to a high of ±450% for OC.

1,828 citations

01 Feb 1995
TL;DR: In this paper, the unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio using DFT, MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set.
Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

1,652 citations