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Nelli D, Pietrucci F, Ferrando R. Impurity diffusion in magic-size icosahedral clusters. J Chem Phys 2021; 155:144304. [PMID: 34654289 DOI: 10.1063/5.0060236] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Atomic diffusion is at the basis of chemical ordering transformations in nanoalloys. Understanding the diffusion mechanisms at the atomic level is therefore a key issue in the study of the thermodynamic behavior of these systems and, in particular, of their evolution from out-of-equilibrium chemical ordering types often obtained in the experiments. Here, the diffusion is studied in the case of a single-atom impurity of Ag or Au moving within otherwise pure magic-size icosahedral clusters of Cu or Co by means of two different computational techniques, i.e., molecular dynamics and metadynamics. Our simulations reveal unexpected diffusion pathways, in which the displacement of the impurity is coupled with the creation of vacancies in the central part of the cluster. We show that the observed mechanism is quite different from the vacancy-mediated diffusion processes identified so far, and we demonstrate that it can be related to the presence of non-homogeneous compressive stress in the inner part of the icosahedral structure.
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Affiliation(s)
- Diana Nelli
- Dipartimento di Fisica dell'Università di Genova, via Dodecaneso 33, Genova 16146, Italy
| | - Fabio Pietrucci
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, IMPMC, 75005 Paris, France
| | - Riccardo Ferrando
- Dipartimento di Fisica dell'Università di Genova and CNR-IMEM, via Dodecaneso 33, Genova 16146, Italy
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2
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Yamazaki T, Van Driessche AES, Kimura Y. High mobility of lattice molecules and defects during the early stage of protein crystallization. SOFT MATTER 2020; 16:1955-1960. [PMID: 31967624 DOI: 10.1039/c9sm02382h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Protein crystals are expected to be useful not only for their molecular structure analysis but also as functional materials due to their unique properties. Although the generation and the propagation of defects during crystallization play critical roles in the final properties of protein crystals, the dynamics of these processes are poorly understood. By time-resolved liquid-cell transmission electron microscopy, we observed that nanosized crystal defects are surprisingly mobile during the early stages of the crystallization of a lysozyme as a model protein. This highly dynamic behavior of defects reveals that the lattice molecules are mobile throughout the crystal structure. Moreover, the disappearance of the defects indicated that intermolecular bonds can break and reform rapidly with little energetic cost, as reported in theoretical studies. All these findings are in marked contrast to the generally accepted notion that crystal lattices are rigid with very limited mobility of individual lattice molecules.
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Affiliation(s)
- Tomoya Yamazaki
- Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo, 060-0819, Japan.
| | - Alexander E S Van Driessche
- Université Grenoble Alpes, Université Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, F-38000, Grenoble, France
| | - Yuki Kimura
- Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo, 060-0819, Japan.
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3
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Structure and Catalytic Behavior of Alumina Supported Bimetallic Au-Rh Nanoparticles in the Reduction of NO by CO. Catalysts 2019. [DOI: 10.3390/catal9110937] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Alumina-supported bimetallic AuRh catalysts, as well as monometallic reference catalysts, were examined with regard to their structural and catalytic properties in the reduction of NO by CO. Depending on the molar ratio of Au:Rh, the nanoparticles prepared by borohydride co-reduction of corresponding metal salt solutions had a size of 3.5–6.7 nm. The particles consisted of well-dispersed noble metal atoms with some enrichment of Rh in their surface region. NO conversion of AuRh/Al2O3 shifted to lower temperatures with increasing Rh content, reaching highest activity and highest N2 selectivity for the monometallic Rh/Al2O3 catalyst. This behavior is attributed to the enhanced adsorption of CO on the bimetallic catalyst resulting in unfavorable cationic Rh clusters Rh+-(CO)2. Doping with ceria of AuRh/Al2O3 and Rh/Al2O3 catalysts increased the surface population of metallic Rh sites, which are considered most active for the reduction of NO by CO and enhancement of the formation of intermediate isocyanate (-NCO) surface species and their reaction with NO to form N2 and CO2.
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4
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Dekura S, Kobayashi H, Kusada K, Kitagawa H. Hydrogen in Palladium and Storage Properties of Related Nanomaterials: Size, Shape, Alloying, and Metal-Organic Framework Coating Effects. Chemphyschem 2019; 20:1158-1176. [PMID: 30887646 DOI: 10.1002/cphc.201900109] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Indexed: 11/07/2022]
Abstract
One of the key issues for an upcoming hydrogen energy-based society is to develop highly efficient hydrogen-storage materials. Among the many hydrogen-storage materials reported, transition-metal hydrides can reversibly absorb and desorb hydrogen, and have thus attracted much interest from fundamental science to applications. In particular, the Pd-H system is a simple and classical metal-hydrogen system, providing a platform suitable for a thorough understanding of ways of controlling the hydrogen-storage properties of materials. By contrast, metal nanoparticles have been recently studied for hydrogen storage because of their unique properties and the degrees of freedom which cannot be observed in bulk, i. e., the size, shape, alloying, and surface coating. In this review, we overview the effects of such degrees of freedom on the hydrogen-storage properties of Pd-related nanomaterials, based on the fundamental science of bulk Pd-H. We shall show that sufficiently understanding the nature of the interaction between hydrogen and host materials enables us to control the hydrogen-storage properties though the electronic-structure control of materials.
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Affiliation(s)
- Shun Dekura
- Division of Chemistry, Graduate School of Science, Kyoto University Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan.,Current address: Institute for Solid State Physics, The University of Tokyo 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8581, Japan
| | - Hirokazu Kobayashi
- Division of Chemistry, Graduate School of Science, Kyoto University Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan.,Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST) Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan
| | - Kohei Kusada
- Division of Chemistry, Graduate School of Science, Kyoto University Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Hiroshi Kitagawa
- Division of Chemistry, Graduate School of Science, Kyoto University Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan.,Inamori Frontier Research Center, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.,Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Yoshida, Sakyo-ku, Kyoto, 606-8501, Japan
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5
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Kusada K, Kitagawa H. A Route for Phase Control in Metal Nanoparticles: A Potential Strategy to Create Advanced Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:1129-1142. [PMID: 26539900 DOI: 10.1002/adma.201502881] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 07/15/2015] [Indexed: 06/05/2023]
Abstract
There is untapped potential for materials whose crystal structures are unobtainable in the bulk state. Several examples of such structures have been found in nanomaterials, and these materials exhibit unique properties that arise from their unique electronic states and surface structures. Here, recent developments in the syntheses of these nanomaterials and their unique properties, such as hydrogen-storage ability and catalytic activity, are summarized. Firstly, the syntheses and properties of novel solid-solution alloy nanoparticles in immiscible alloy systems such as Ag-Rh and Pd-Ru are introduced. Following this, the crystal structure control of nanoscale Ru is discussed. These unique alloy materials show enhanced properties and highlight the potential of phase control to be a new strategy for nanomaterial development.
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Affiliation(s)
- Kohei Kusada
- Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan
- JST CREST, 7 Goban-cho, Chiyoda-ku, Tokyo, 102-0076, Japan
| | - Hiroshi Kitagawa
- Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto, 606-8502, Japan
- JST CREST, 7 Goban-cho, Chiyoda-ku, Tokyo, 102-0076, Japan
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6
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Kobayashi H, Kusada K, Kitagawa H. Creation of Novel Solid-Solution Alloy Nanoparticles on the Basis of Density-of-States Engineering by Interelement Fusion. Acc Chem Res 2015; 48:1551-9. [PMID: 25993560 DOI: 10.1021/ar500413e] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Currently 118 known elements are represented in the periodic table. Of these 118 elements, only about 80 elements are stable, nonradioactive, and widely available for our society. From the viewpoint of the "elements strategy", we need to make full use of the 80 elements to bring out their latent ability and create innovative materials. Furthermore, there is a strong demand that the use of rare or toxic elements be reduced or replaced while their important properties are retained. Advanced science and technology could create higher-performance materials even while replacing or reducing minor or harmful elements through the combination of more abundant elements. The properties of elements are correlated directly with their electronic states. In a solid, the magnitude of the density of states (DOS) at the Fermi level affects the physical and chemical properties. In the present age, more attention has been paid to improving the properties of materials by means of alloying elements. In particular, the solid-solution-type alloy is advantageous because the properties can be continuously controlled by tuning the compositions and/or combinations of the constituent elements. However, the majority of bulk alloys are of the phase-separated type under ambient conditions, where constituent elements are immiscible with each other. To overcome the challenge of the bulk-phase metallurgical aspects, we have focused on the nanosize effect and developed methods involving "nonequilibrium synthesis" or "a process of hydrogen absorption/desorption". We propose a new concept of "density-of-states engineering" for the design of materials having the most desirable and suitable properties by means of "interelement fusion". In this Account, we describe novel solid-solution alloys of Pd-Pt, Ag-Rh, and Pd-Ru systems in which the constituent elements are immiscible in the bulk state. The homogeneous solid-solution alloys of Pd and Pt were created from Pd core/Pt shell nanoparticles using a hydrogen absorption/desorption process as a trigger. Several atom percent replacements of Pd with Pt atoms resulted in a significantly enhanced hydrogen absorption capacity compared with Pd nanoparticles. AgxRh1-x and PdxRu1-x solid-solution alloy nanoparticles were also developed by nonequilibrium synthesis based on a polyol method. The AgxRh1-x nanoparticles demonstrated hydrogen storage properties, although pure metal nanoparticles of each constituent element do not adsorb hydrogen. AgxRh1-x is therefore considered to possess a similar electronic structure to Pd as a synthetic pseudo-palladium. The PdxRu1-x nanoparticles showed enhanced catalytic activity for CO oxidation, with the highest catalytic activity found using the equimolar Pd0.5Ru0.5 nanoparticles. The catalytic activity of the Pd0.5Ru0.5 nanoparticles exceeds that of the widely used and best-performing Ru catalysts for CO oxidation and is also higher than that of neighboring Rh on the periodic table. Our present work provides a guiding principle for the design of a suitable DOS shape according to the intended physical and/or chemical properties and a method for the development of novel solid-solution alloys.
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Affiliation(s)
- Hirokazu Kobayashi
- Division
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho,
Sakyo-ku, Kyoto 606-8502, Japan
- CREST, Japan Science and Technology Agency (JST), 7 Goban-cho, Chiyoda-ku, Tokyo 102-0076, Japan
| | - Kohei Kusada
- Division
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho,
Sakyo-ku, Kyoto 606-8502, Japan
- CREST, Japan Science and Technology Agency (JST), 7 Goban-cho, Chiyoda-ku, Tokyo 102-0076, Japan
| | - Hiroshi Kitagawa
- Division
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho,
Sakyo-ku, Kyoto 606-8502, Japan
- CREST, Japan Science and Technology Agency (JST), 7 Goban-cho, Chiyoda-ku, Tokyo 102-0076, Japan
- Institute
for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan
- INAMORI
Frontier Research Center, Kyushu University, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan
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7
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Sinha SK, Srivastava C, Sampath S, Chattopadhyay K. Tunability of monodispersed intermetallic AuCu nanoparticles through understanding of reaction pathways. RSC Adv 2015. [DOI: 10.1039/c4ra12059k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Methodologies for the synthesis of size selective monodisperse AuCu intermetallic nanoparticles have been provided.
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Affiliation(s)
- S. K. Sinha
- Department of Materials Engineering
- Indian Institute of Science
- Bangalore-560 012
- India
| | - C. Srivastava
- Department of Materials Engineering
- Indian Institute of Science
- Bangalore-560 012
- India
| | - S. Sampath
- Department of Inorganic and Physical Chemistry
- Indian Institute of Science
- Bangalore-560 012
- India
| | - K. Chattopadhyay
- Department of Materials Engineering
- Indian Institute of Science
- Bangalore-560 012
- India
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8
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Zhang H, Haba M, Okumura M, Akita T, Hashimoto S, Toshima N. Novel formation of Ag/Au bimetallic nanoparticles by physical mixture of monometallic nanoparticles in dispersions and their application to catalysts for aerobic glucose oxidation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:10330-10339. [PMID: 23829515 DOI: 10.1021/la401878g] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Ag/Au bimetallic nanoparticles (BNPs) with a size less than 2 nm were prepared by physical mixture of colloidal dispersions of Ag and Au nanoparticles (NPs). This provides an example of fabrication of BNPs with self-organization by the reaction between metal NPs. Although Ag/Au BNPs having different structures and compositions are one of the most widely studied bimetallic systems in the literature due to their wide range of uses such as in catalysis, electronics, plasmonics, optical sensing, and surface-enhanced Raman scattering, we first prepared such BNPs by physical mixture and characterized them by UV-vis spectroscopy, SERS, XPS, TEM, and EDS in HR-STEM. The present fabrication method has the advantage of avoiding the unfavorable formation of AgCl precipitates in the reaction process which are always produced when Ag(+) ions are used as a starting material in combination with a HAuCl4 precursor. These Ag/Au BNPs showed high catalytic activities for aerobic glucose oxidation, and the highest activity of 11,510 mol of glucose·h(-1)·mol of metal(-1) was observed for the BNPs with a Ag/Au atomic ratio of 1/4; the activity value is about 2 times higher than that of Au NPs with nearly the same particle size. XPS and DFT calculation results show that the negatively charged Au atoms due to the electron charge transfer effects from neighboring Ag atoms and poly(N-vinyl-2-pyrrolidone) act as catalytically active sites and play an important role in the aerobic glucose oxidation.
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Affiliation(s)
- Haijun Zhang
- College of Materials & Metallurgy, Wuhan University of Science and Technology, Wuhan, Hubei Province 430081, China
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9
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MORI H, YASUDA H. Observation by TEM of spontaneous alloying in nanometre-sized atom clusters in the Au-Al system. J Microsc 2011. [DOI: 10.1111/j.1365-2818.1995.tb03654.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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11
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Tran DT, Jones IP, Johnston RL, Preece JA, Brom CRVD. Truncated-octahedral copper-gold nanoparticles. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/241/1/012086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Niiyama T, Shimizu Y, Kobayashi TR, Okushima T, Ikeda KS. Effect of translational and angular momentum conservation on energy equipartition in microcanonical equilibrium in small clusters. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:051101. [PMID: 19518410 DOI: 10.1103/physreve.79.051101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Indexed: 05/27/2023]
Abstract
We investigate numerically and analytically the effects of conservation of total translational and angular momentum on the distribution of kinetic energy among particles in microcanonical particle systems with small number of degrees of freedom, specifically microclusters. Molecular dynamics simulations of microclusters with constant total energy and momenta, using Lennard-Jones, Morse, and Coulomb plus Born-Mayer-type potentials, show that the distribution of kinetic energy among particles can be inhomogeneous and depend on particle mass and position even in thermal equilibrium. Statistical analysis using a microcanonical measure taking into account of the additional conserved quantities gives theoretical expressions for kinetic energy as a function of the mass and position of a particle with only O(1/N;{2}) deviation from the Maxwell-Boltzmann distribution. These expressions fit numerical results well. Finally, we propose an intuitive interpretation for the inhomogeneity of the kinetic energy distributions.
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Affiliation(s)
- Tomoaki Niiyama
- Department of Physics, Ritsumeikan University, Noji-higashi 1-1-1, Kusatsu 525-8577, Japan
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13
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Yasuda H, Tanaka A, Matsumoto K, Nitta N, Mori H. Formation of porous GaSb compound nanoparticles by electronic-excitation-induced vacancy clustering. PHYSICAL REVIEW LETTERS 2008; 100:105506. [PMID: 18352206 DOI: 10.1103/physrevlett.100.105506] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Indexed: 05/26/2023]
Abstract
Porous semiconductor compound nanoparticles have been prepared by a new technique utilizing electronic excitation. The porous structures are formed in GaSb particles, when vacancies are efficiently introduced by electronic excitation and the particle size is large enough to confine the vacancy clusters. The capture cross section of the surface layer in particles for the vacancies is smaller than that for the interstitials. Under the condition of supersaturation of vacancies in the particle core, porous structures are produced through the vacancy clusters to a void formation.
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Affiliation(s)
- H Yasuda
- Department of Mechanical Engineering, Kobe University, Rokkodai, Nada, Kobe 657-8501, Japan.
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14
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Ferrando R, Jellinek J, Johnston RL. Nanoalloys: From Theory to Applications of Alloy Clusters and Nanoparticles. Chem Rev 2008; 108:845-910. [PMID: 18335972 DOI: 10.1021/cr040090g] [Citation(s) in RCA: 1707] [Impact Index Per Article: 106.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Riccardo Ferrando
- Dipartimento di Fisica, Universita di Genova, INFM and IMEM/CNR, Via Dodecaneso 33, Genova, I16146, Italy, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Julius Jellinek
- Dipartimento di Fisica, Universita di Genova, INFM and IMEM/CNR, Via Dodecaneso 33, Genova, I16146, Italy, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Roy L. Johnston
- Dipartimento di Fisica, Universita di Genova, INFM and IMEM/CNR, Via Dodecaneso 33, Genova, I16146, Italy, Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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15
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Toai TJ, Rossi G, Ferrando R. Global optimisation and growth simulation of AuCu clusters. Faraday Discuss 2008; 138:49-58; discussion 119-35, 433-4. [DOI: 10.1039/b707813g] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Grigorieva TF, Barinova AP, Lyakhov NZ. Mechanochemical synthesis of intermetallic compounds. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc2001v070n01abeh000598] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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17
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Niiyama T, Shimizu Y, Kobayashi TR, Okushima T, Ikeda KS. Inhomogeneity of local temperature in small clusters in microcanonical equilibrium. PHYSICAL REVIEW LETTERS 2007; 99:014102. [PMID: 17678154 DOI: 10.1103/physrevlett.99.014102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Indexed: 05/16/2023]
Abstract
Overall homogeneity of temperature is a condition for thermal equilibrium, but, as is demonstrated by classical molecular dynamics simulations, the local temperatures of atoms in small, isolated crystalline clusters in microcanonical equilibrium are not uniform. The effective temperature determined from individual atomic velocity decreases with distance from the cluster center. It is argued that these effects are due to the conservation of angular and translational momentum. A general microcanonical expression is derived for the spatial dependence of the statistics of the kinetic energies of individual atoms; this fits the numerical observations well.
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Affiliation(s)
- Tomoaki Niiyama
- Department of Physics, Ritsumeikan University, Kusatsu, Japan
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18
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Yasuda H, Mori H, Lee JG. Nonlinear responses of electronic-excitation-induced phase transformations in GaSb nanoparticles. PHYSICAL REVIEW LETTERS 2004; 92:135501. [PMID: 15089621 DOI: 10.1103/physrevlett.92.135501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2003] [Indexed: 05/24/2023]
Abstract
We studied electronic-excitation-induced phase transformations in nanoparticles using transmission electron microscopy. GaSb particles excited by 75 keV electrons transform to two phases consisting of an antimony core and a gallium shell or an amorphous phase, or remain in the original crystalline phase, depending on particle size and/or temperature. It is suggested that such nonlinear responses of the phase transformations may arise from synergistic effects of bond instability, localized excitations, enhanced diffusivity, or thermal equilibrium in reactions.
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Affiliation(s)
- H Yasuda
- Department of Mechanical Engineering, Kobe University, Rokkodai, Nada, Kobe 657-8501, Japan.
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19
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Wilson NT, Johnston RL. A theoretical study of atom ordering in copper–gold nanoalloy clusters. ACTA ACUST UNITED AC 2002. [DOI: 10.1039/b204069g] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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López MJ, Marcos PA, Alonso JA. Structural and dynamical properties of Cu–Au bimetallic clusters. J Chem Phys 1996. [DOI: 10.1063/1.470831] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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