101
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Lazauskas T, Sokol AA, Woodley SM. An efficient genetic algorithm for structure prediction at the nanoscale. NANOSCALE 2017; 9:3850-3864. [PMID: 28252128 DOI: 10.1039/c6nr09072a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We have developed and implemented a new global optimization technique based on a Lamarckian genetic algorithm with the focus on structure diversity. The key process in the efficient search on a given complex energy landscape proves to be the removal of duplicates that is achieved using a topological analysis of candidate structures. The careful geometrical prescreening of newly formed structures and the introduction of new mutation move classes improve the rate of success further. The power of the developed technique, implemented in the Knowledge Led Master Code, or KLMC, is demonstrated by its ability to locate and explore a challenging double funnel landscape of a Lennard-Jones 38 atom system (LJ38). We apply the redeveloped KLMC to investigate three chemically different systems: ionic semiconductor (ZnO)1-32, metallic Ni13 and covalently bonded C60. All four systems have been systematically explored on the energy landscape defined using interatomic potentials. The new developments allowed us to successfully locate the double funnels of LJ38, find new local and global minima for ZnO clusters, extensively explore the Ni13 and C60 (the buckminsterfullerene, or buckyball) potential energy surfaces.
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Affiliation(s)
- Tomas Lazauskas
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Alexey A Sokol
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, UK.
| | - Scott M Woodley
- University College London, Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, UK.
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102
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103
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Abstract
Metal ions play significant roles in numerous fields including chemistry, geochemistry, biochemistry, and materials science. With computational tools increasingly becoming important in chemical research, methods have emerged to effectively face the challenge of modeling metal ions in the gas, aqueous, and solid phases. Herein, we review both quantum and classical modeling strategies for metal ion-containing systems that have been developed over the past few decades. This Review focuses on classical metal ion modeling based on unpolarized models (including the nonbonded, bonded, cationic dummy atom, and combined models), polarizable models (e.g., the fluctuating charge, Drude oscillator, and the induced dipole models), the angular overlap model, and valence bond-based models. Quantum mechanical studies of metal ion-containing systems at the semiempirical, ab initio, and density functional levels of theory are reviewed as well with a particular focus on how these methods inform classical modeling efforts. Finally, conclusions and future prospects and directions are offered that will further enhance the classical modeling of metal ion-containing systems.
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Affiliation(s)
| | - Kenneth M. Merz
- Department of Chemistry, Department of Biochemistry and Molecular Biology, and Institute of Cyber-Enabled Research, Michigan State University, East Lansing, Michigan 48824, United States
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104
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Fan YC, Fang TH, Lin KM, Qiu RZ. Nanoindentation and Deformation of Multilayered Au/Cu Films. SMART SCIENCE 2017. [DOI: 10.1080/23080477.2016.1275933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Yu-Cheng Fan
- Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan
| | - Te-Hua Fang
- Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan
| | - Kuan-Ming Lin
- Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan
| | - Ren-Zheng Qiu
- Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan
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105
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Vesselli E, Peressi M. Nanoscale Control of Metal Clusters on Templating Supports. STUDIES IN SURFACE SCIENCE AND CATALYSIS 2017. [DOI: 10.1016/b978-0-12-805090-3.00008-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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106
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Gulenko A, Forto Chungong L, Gao J, Todd I, Hannon AC, Martin RA, Christie JK. Atomic structure of Mg-based metallic glasses from molecular dynamics and neutron diffraction. Phys Chem Chem Phys 2017; 19:8504-8515. [DOI: 10.1039/c6cp03261c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We use a combination of classical molecular dynamics simulation and neutron diffraction to identify the atomic structure of five different Mg–Zn–Ca bulk metallic glasses, covering a range of compositions with substantially different behaviour when implantedin vitro.
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Affiliation(s)
| | - Louis Forto Chungong
- Aston Institute of Materials Research
- School of Engineering and Applied Sciences & Aston Research Centre for Healthy Ageing University of Aston Birmingham
- UK
| | - Junheng Gao
- Faculty of Engineering
- University of Sheffield
- Sheffield
- UK
| | - Iain Todd
- Faculty of Engineering
- University of Sheffield
- Sheffield
- UK
| | | | - Richard A. Martin
- Aston Institute of Materials Research
- School of Engineering and Applied Sciences & Aston Research Centre for Healthy Ageing University of Aston Birmingham
- UK
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107
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Naskar P, Talukder S, Chaudhury P. An adaptive mutation simulated annealing based investigation of Coulombic explosion and identification of dissociation patterns in (CO2)n2+ clusters. Phys Chem Chem Phys 2017; 19:9654-9668. [DOI: 10.1039/c7cp00655a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this communication, we would like to discuss the advantages of adaptive mutation simulated annealing (AMSA) over standard simulated annealing (SA) in studying the Coulombic explosion of (CO2)n2+ clusters for n = 20–68, where ‘n’ is the size of the cluster.
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Affiliation(s)
- Pulak Naskar
- Department of Chemistry
- University of Calcutta
- Kolkata – 700 009
- India
| | - Srijeeta Talukder
- Department of Physical Chemistry
- Indian Association for the Cultivation of Science
- Kolkata – 700 032
- India
| | - Pinaki Chaudhury
- Department of Chemistry
- University of Calcutta
- Kolkata – 700 009
- India
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108
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Carles R, Benzo P, Pécassou B, Bonafos C. Vibrational density of states and thermodynamics at the nanoscale: the 3D-2D transition in gold nanostructures. Sci Rep 2016; 6:39164. [PMID: 27982080 PMCID: PMC5159851 DOI: 10.1038/srep39164] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/17/2016] [Indexed: 11/10/2022] Open
Abstract
Surface enhanced Raman scattering (SERS) is generally and widely used to enhance the vibrational fingerprint of molecules located at the vicinity of noble metal nanoparticles. In this work, SERS is originally used to enhance the own vibrational density of states (VDOS) of nude and isolated gold nanoparticles. This offers the opportunity of analyzing finite size effects on the lattice dynamics which remains unattainable with conventional techniques based on neutron or x-ray inelastic scattering. By reducing the size down to few nanometers, the role of surface atoms versus volume atoms become dominant, and the “text-book” 3D-2D transition on the dynamical behavior is experimentally emphasized. “Anomalies” that have been predicted by a large panel of simulations at the atomic scale, are really observed, like the enhancement of the VDOS at low frequencies or the occurrence of localized modes at frequencies beyond the cut-off in bulk. Consequences on the thermodynamic properties at the nanoscale, like the reduction of the Debye temperature or the excess of the specific heat, have been evaluated. Finally the high sensitivity of reminiscent bulk-like phonons on the arrangements at the atomic scale is used to access the morphology and internal disorder of the nanoparticles.
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Affiliation(s)
- R Carles
- CEMES-CNRS Université de Toulouse, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France
| | - P Benzo
- CEMES-CNRS Université de Toulouse, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France
| | - B Pécassou
- CEMES-CNRS Université de Toulouse, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France
| | - C Bonafos
- CEMES-CNRS Université de Toulouse, rue Jeanne Marvig, BP 94347, 31055 Toulouse Cedex 4, France
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109
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Baidyshev VS, Gafner YY. Formation of structure in small lead clusters under thermal effect. CRYSTALLOGR REP+ 2016. [DOI: 10.1134/s1063774516070038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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110
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Li M, Zhao Z, Cheng T, Fortunelli A, Chen CY, Yu R, Zhang Q, Gu L, Merinov BV, Lin Z, Zhu E, Yu T, Jia Q, Guo J, Zhang L, Goddard WA, Huang Y, Duan X. Ultrafine jagged platinum nanowires enable ultrahigh mass activity for the oxygen reduction reaction. Science 2016; 354:1414-1419. [DOI: 10.1126/science.aaf9050] [Citation(s) in RCA: 1034] [Impact Index Per Article: 129.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 08/25/2016] [Accepted: 10/26/2016] [Indexed: 11/02/2022]
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111
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Gould AL, Rossi K, Catlow CRA, Baletto F, Logsdail AJ. Controlling Structural Transitions in AuAg Nanoparticles through Precise Compositional Design. J Phys Chem Lett 2016; 7:4414-4419. [PMID: 27781433 DOI: 10.1021/acs.jpclett.6b02181] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a study of the transitional pathways between high-symmetry structural motifs for AgAu nanoparticles, with a specific focus on controlling the energetic barriers through chemical design. We show that the barriers can be altered by careful control of the elemental composition and chemical arrangement, with core@shell and vertex-decorated arrangements being specifically influential on the barrier heights. We also highlight the complexity of the potential and free energy landscapes for systems where there are low-symmetry geometric motifs that are energetically competitive to the high-symmetry arrangements. In particular, we highlight that some core@shell arrangements preferentially transition through multistep restructuring of low-symmetry truncated octahedra and rosette-icosahedra, instead of via the more straightforward square-diamond transformations, due to lower energy barriers and competitive energetic minima. Our results have promising implications for the continuing efforts in bespoke nanoparticle design for catalytic and plasmonic applications.
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Affiliation(s)
- Anna L Gould
- University College London , Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- The U.K. Catalysis Hub , Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire OX11 0FA, United Kingdom
| | - Kevin Rossi
- Physics Department, King's College London , London WC2R 2LS, United Kingdom
| | - C Richard A Catlow
- University College London , Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- The U.K. Catalysis Hub , Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire OX11 0FA, United Kingdom
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University , Cardiff CF10 3AT, United Kingdom
| | - Francesca Baletto
- Physics Department, King's College London , London WC2R 2LS, United Kingdom
| | - Andrew J Logsdail
- University College London , Kathleen Lonsdale Materials Chemistry, Department of Chemistry, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University , Cardiff CF10 3AT, United Kingdom
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112
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Husic BE, Schebarchov D, Wales DJ. Impurity effects on solid-solid transitions in atomic clusters. NANOSCALE 2016; 8:18326-18340. [PMID: 27775141 DOI: 10.1039/c6nr06299g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We use the harmonic superposition approach to examine how a single atom substitution affects low-temperature anomalies in the vibrational heat capacity (CV) of model nanoclusters. Each anomaly is linked to competing solidlike "phases", where crossover of the corresponding free energies defines a solid-solid transition temperature (Ts). For selected Lennard-Jones clusters we show that Ts and the corresponding CV peak can be tuned over a wide range by varying the relative atomic size and binding strength of the impurity, but excessive atom-size mismatch can destroy a transition and may produce another. In some tunable cases we find up to two additional CV peaks emerging below Ts, signalling one- or two-step delocalisation of the impurity within the ground-state geometry. Results for Ni74X and Au54X clusters (X = Au, Ag, Al, Cu, Ni, Pd, Pt, Pb), modelled by the many-body Gupta potential, further corroborate the possibility of tuning, engineering, and suppressing finite-system analogues of a solid-solid transition in nanoalloys.
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Affiliation(s)
- B E Husic
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK. and Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
| | - D Schebarchov
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK.
| | - D J Wales
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK.
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113
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Sukhomlinov SV, Müser MH. Constraints on phase stability, defect energies, and elastic constants of metals described by EAM-type potentials. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:395701. [PMID: 27465401 DOI: 10.1088/0953-8984/28/39/395701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate that the embedded-atom method and related potentials predict many dimensionless properties of simple metals to depend predominantly on a single coefficient μ, which typically lies between 0.3 and 0.45. Among other relations presented in this work, we find that [Formula: see text], [Formula: see text], and [Formula: see text] hold within 25% accuracy and also find a linear dependence of the melting temperature on μ. The used variables are cohesive energy E c, coordination number Z, vacancy energy E v, and bulk modulus B, while G is the average of ordinary and tetragonal shear modulus. We provide analytical arguments for these findings, which are obeyed reasonably well by several metals.
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Affiliation(s)
- Sergey V Sukhomlinov
- John von Neumann Institute for Computing and Jülich Supercomputing Centre, FZ Jülich, 52425 Jülich, Germany
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114
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Wu X, Wei Z, Sun Y, Feng YL, Liu QM. Influence of the potential model parameters on the structures and potential energy surface of cobalt clusters. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.07.056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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115
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Theoretical Study on the Structures and Thermal Properties of Ag–Pt–Ni Trimetallic Clusters. J CLUST SCI 2016. [DOI: 10.1007/s10876-016-1068-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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116
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Wei GF, Liu ZP. Subnano Pt Particles from a First-Principles Stochastic Surface Walking Global Search. J Chem Theory Comput 2016; 12:4698-706. [DOI: 10.1021/acs.jctc.6b00556] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Guang-Feng Wei
- Shanghai
Key Laboratory of Chemical Assessment and Sustainability, Department
of Chemistry, Tongji University, Shanghai 200092, China
- Collaborative
Innovation Center of Chemistry for Energy Material, Shanghai Key Laboratory
of Molecular Catalysis and Innovative Materials, Key Laboratory of
Computational Physical Science (Ministry of Education), Department
of Chemistry, Fudan University, Shanghai 200433, China
| | - Zhi-Pan Liu
- Collaborative
Innovation Center of Chemistry for Energy Material, Shanghai Key Laboratory
of Molecular Catalysis and Innovative Materials, Key Laboratory of
Computational Physical Science (Ministry of Education), Department
of Chemistry, Fudan University, Shanghai 200433, China
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117
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Samsonov VM, Chernyshova AA. On the size dependence of the surface energy of metal nanoclusters. COLLOID JOURNAL 2016. [DOI: 10.1134/s1061933x16030145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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118
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Sushko GB, Verkhovtsev AV, Kexel C, Korol AV, Schramm S, Solov'yov AV. Reconciling simulated melting and ground-state properties of metals with a modified embedded-atom method potential. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:145201. [PMID: 26977922 DOI: 10.1088/0953-8984/28/14/145201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We propose a modification of the embedded-atom method-type potential aiming at reconciling simulated melting and ground-state properties of metals by means of classical molecular dynamics. Considering titanium, magnesium, gold, and platinum as case studies, we demonstrate that simulations performed with the modified force field yield quantitatively correctly both the melting temperature of the metals and their ground-state properties. It is shown that the accounting for the long-range interatomic interactions noticeably affects the melting point assessment. The introduced modification weakens the interaction at interatomic distances exceeding the equilibrium one by a characteristic vibration amplitude defined by the Lindemann criterion, thus allowing for the correct simulation of melting, while keeping its behavior in the vicinity of the ground state minimum. The modification of the many-body potential has a general nature and can be applicable to metals with different characteristics of the electron structure as well as for many different molecular and solid state systems experiencing phase transitions.
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119
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Structural, Energetic, and Magnetic Properties of Ag $$_{n-m}$$ n - m Rh $$_{m}$$ m and Ag $$_{m}$$ m Rh $$_{n-m}$$ n - m Clusters with $$n \le 20$$ n ≤ 20 and $$m=0,1$$ m = 0 , 1. J CLUST SCI 2016. [DOI: 10.1007/s10876-016-1003-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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120
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Zhao Z, Fisher A, Cheng D. Phase diagram and segregation of Ag-Co nanoalloys: insights from theory and simulation. NANOTECHNOLOGY 2016; 27:115702. [PMID: 26876185 DOI: 10.1088/0957-4484/27/11/115702] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Understanding the phase diagram is the first step to identifying the structure-performance relationship of a material at the nanoscale. In this work, a modified nanothermodynamical model has been developed to predict the phase diagrams of Ag-Co nanoalloys with the size of 1 ∼ 100 nm, which also overcomes the difference in the predicted results between theory and simulation for the first time. Based on this modified model, the phase diagrams of Ag-Co nanoalloys with various polyhedral morphologies (tetrahedron, cube, octahedron, decahedron, dodecahedron, rhombic dodecahedron, truncated octahedron, cuboctahedron, and icosahedron) have been predicted, showing good agreement with molecular dynamics simulations at the nanoscale of 1 ∼ 4 nm. In addition, the surface segregation of Ag-Co nanoalloys has been predicted with a Co-rich core/Ag-rich surface, which is also consistent with the simulation results. Our results highlight a useful roadmap for bridging the difference between theory and simulation in the prediction of the phase diagram at the nanoscale, which will help both theorists and experimentalists.
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Affiliation(s)
- Zheng Zhao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
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121
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Mo J, Li L, Wang J, Li Z. Passive fluidic diode for simple fluids using nested nanochannel structures. Phys Rev E 2016; 93:033101. [PMID: 27078441 DOI: 10.1103/physreve.93.033101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 06/05/2023]
Abstract
In this paper, we propose a moving part-free fluidic diode for simple fluids using nested nanochannels, which contain inner and outer channels of different lengths. Molecular dynamics simulations show that the fluidic diode accepts water flows in the forward direction and blocks flows in the backward direction in a wide range of pressure drops. The anisotropic flow rates are generated by the distinct activation pressures in different directions. In the forward direction, the activation pressure is low, which is determined by the infiltration pressure of the inner channel. In the backward direction, the activation pressure is quite high due to the capillary effects when flows are released from the inner to the outer channel. The pressure drop range for the fluidic diode can be varied by changing the channel size or surface wettability. The fluidic diode offers an alternative way for flow control in integrated micro- and nanofluidic devices.
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Affiliation(s)
- Jingwen Mo
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Long Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jun Wang
- Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, People's Republic of China
| | - Zhigang Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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122
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De Clercq A, Giorgio S, Mottet C. Pd surface and Pt subsurface segregation in Pt1-c Pd c nanoalloys. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:064006. [PMID: 26795206 DOI: 10.1088/0953-8984/28/6/064006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The structure and chemical arrangement of Pt1-c Pd c nanoalloys with the icosahedral and face centered cubic symmetry are studied using Monte Carlo simulations with a tight binding interatomic potential fitted to density-functional theory calculations. Pd surface segregation from the lowest to the highest coordinated sites is predicted by the theory together with a Pt enrichment at the subsurface, whatever the structure and the size of the nanoparticles, and which subsists when increasing the temperature. The onion-shell chemical configuration is found for both symmetries and is initiated from the Pd surface segregation. It is amplified in the icosahedral symmetry and small sizes but when considering larger sizes, the oscillating segregation profile occurs near the surface on about three to four shells whatever the structure. Pd segregation results from the significant lower cohesive energy of Pd as compared to Pt and the weak ordering tendency leads to the Pt subsurface segregation. The very weak size mismatch does not prevent the bigger atoms (Pt) from occupying subsurface sites which are in compression whereas the smaller ones (Pd) occupy the central site of the icosahedra where the compression is an order of magnitude higher.
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Affiliation(s)
- A De Clercq
- Aix Marseille Université, CNRS, CINaM UMR7325, Campus de Luminy, F-13288 Marseille, France. Aix Marseille Université, CNRS, MADIREL UMR7246, 13397 Marseille, France
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123
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Zhao Z, Fisher A, Shen Y, Cheng D. Magnetic Properties of Pt-Based Nanoalloys: A Critical Review. J CLUST SCI 2016. [DOI: 10.1007/s10876-016-0983-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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124
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Sharmila DJS, Jino Blessy J. Molecular dynamics of sialic acid analogues complex with cholera toxin and DFT optimization of ethylene glycol-mediated zinc nanocluster conjugation. J Biomol Struct Dyn 2016; 35:182-206. [PMID: 26733187 DOI: 10.1080/07391102.2015.1136689] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Cholera is an infectious disease caused by cholera toxin (CT) protein of bacterium Vibrio cholerae. A sequence of sialic acid (N-acetylneuraminic acid, NeuNAc or Neu5Ac) analogues modified in its C-5 position is modelled using molecular modelling techniques and docked against the CT followed by molecular dynamics simulations. Docking results suggest better binding affinity of NeuNAc analogue towards the binding site of CT. The NeuNAc analogues interact with the active site residues GLU:11, TYR:12, HIS:13, GLY:33, LYS:34, GLU:51, GLN:56, HIE:57, ILE:58, GLN:61, TRP:88, ASN:90 and LYS:91 through intermolecular hydrogen bonding. Analogues N-glycolyl-NeuNAc, N-Pentanoyl-NeuNAc and N-Propanoyl-NeuNAc show the least XPGscore (docking score) of -9.90, -9.16, and -8.91, respectively, and glide energy of -45.99, -42.14 and -41.66 kcal/mol, respectively. Stable nature of CT-N-glycolyl-NeuNAc, CT-N-Pentanoyl-NeuNAc and CT-N-Propanoyl-NeuNAc complexes was verified through molecular dynamics simulations, each for 40 ns using the software Desmond. All the nine NeuNAc analogues show better score for drug-like properties, so could be considered as suitable candidates for drug development for cholera infection. To improve the enhanced binding mode of NeuNAc analogues towards CT, the nine NeuNAc analogues are conjugated with Zn nanoclusters through ethylene glycol (EG) as carriers. The NeuNAc analogues conjugated with EG-Zn nanoclusters show better binding energy towards CT than the unconjugated nine NeuNAc analogues. The electronic structural optimization of EG-Zn nanoclusters was carried out for optimizing their performance as better delivery vehicles for NeuNAc analogues through density functional theory calculations. These sialic acid analogues may be considered as novel leads for the design of drug against cholera and the EG-Zn nanocluster may be a suitable carrier for sialic acid analogues.
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Affiliation(s)
- D Jeya Sundara Sharmila
- a Department of Nano Science and Technology , Tamil Nadu Agricultural University , Coimbatore 641003 , Tamil Nadu , India
| | - J Jino Blessy
- b Department of Bioinformatics , Karunya University , Karunya Nagar, Coimbatore 641 114 , Tamil Nadu , India
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125
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Ali S, Myasnichenko VS, Neyts EC. Size-dependent strain and surface energies of gold nanoclusters. Phys Chem Chem Phys 2016; 18:792-800. [DOI: 10.1039/c5cp06153a] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Calculation of size-dependent strain and surface energies of gold nanoparticles.
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Affiliation(s)
- S. Ali
- Research Group PLASMANT
- Department of Chemistry
- University of Antwerp
- 2610 Wilrijk-Antwerp
- Belgium
| | | | - E. C. Neyts
- Research Group PLASMANT
- Department of Chemistry
- University of Antwerp
- 2610 Wilrijk-Antwerp
- Belgium
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126
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Paiva MAM, Peluzo BMTC, Belchior JC, Galvão BRL. Structure and stability of neutral Al–Mg nanoclusters up to 55 atoms. Phys Chem Chem Phys 2016; 18:31579-31585. [DOI: 10.1039/c6cp05605a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The geometries of aluminum–magnesium nanoalloys are explored using a genetic algorithm tuned to search for the 10 lowest energy minima for each cluster size and composition.
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Affiliation(s)
- Mateus A. M. Paiva
- Departamento de Química
- Centro Federal de Educação Tecnológica de Minas Gerais
- CEFET-MG
- Minas Gerais
- Brazil
| | - Bárbara M. T. C. Peluzo
- Departamento de Química
- Centro Federal de Educação Tecnológica de Minas Gerais
- CEFET-MG
- Minas Gerais
- Brazil
| | - Jadson C. Belchior
- Departamento de Química-ICEx
- Universidade Federal de Minas Gerais
- Minas Gerais
- Brazil
| | - Breno R. L. Galvão
- Departamento de Química
- Centro Federal de Educação Tecnológica de Minas Gerais
- CEFET-MG
- Minas Gerais
- Brazil
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127
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Kohaut S, Springborg M. Growth patterns and structural motifs of cadmium clusters with up to 60 atoms: disordered or not? Phys Chem Chem Phys 2016; 18:28524-28537. [DOI: 10.1039/c6cp04948f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A new growth pattern in small to medium-sized cadmium clusters based on the Leary tetrahedron is predicted.
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Affiliation(s)
- Stephan Kohaut
- Physical and Theoretical Chemistry
- University of Saarland
- Saarbrücken
- Germany
| | - Michael Springborg
- Physical and Theoretical Chemistry
- University of Saarland
- Saarbrücken
- Germany
- School of Materials Science and Engineering
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128
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Dessens-Félix M, Pacheco-Contreras R, Cabrera-Trujillo J, Montejano-Carrizales J, Paz-Borbón LO, Fortunelli A, Posada-Amarillas A. Exploring the energy landscape of Pt Au115− nanoalloys. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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129
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Atomistic Design of Favored Compositions for Synthesizing the Al-Ni-Y Metallic Glasses. Sci Rep 2015; 5:16218. [PMID: 26592568 PMCID: PMC4655373 DOI: 10.1038/srep16218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 10/12/2015] [Indexed: 11/08/2022] Open
Abstract
For a ternary alloy system promising for obtaining the so-called bulk metallic glasses (BMGs), the first priority issue is to predict the favored compositions, which could then serve as guidance for the appropriate alloy design. Taking the Al-Ni-Y system as an example, here we show an atomistic approach, which is developed based on a recently constructed and proven realistic interatomic potential of the system. Applying the Al-Ni-Y potential, series simulations not only clarify the glass formation mechanism, but also predict in the composition triangle, a hexagonal region, in which a disordered state, i.e., the glassy phase, is favored energetically. The predicted region is defined as glass formation region (GFR) for the ternary alloy system. Moreover, the approach is able to calculate an amorphization driving force (ADF) for each possible glassy alloy located within the GFR. The calculations predict an optimized sub-region nearby a stoichiometry of Al80Ni5Y15, implying that the Al-Ni-Y metallic glasses designed in the sub-region could be the most stable. Interestingly, the atomistic predictions are supported by experimental results observed in the Al-Ni-Y system. In addition, structural origin underlying the stability of the Al-Ni-Y metallic glasses is also discussed in terms of a hybrid packing mode in the medium-range scale.
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130
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Pavan L, Rossi K, Baletto F. Metallic nanoparticles meet metadynamics. J Chem Phys 2015; 143:184304. [DOI: 10.1063/1.4935272] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- L. Pavan
- Physics Department, King’s College London, London WC2R 2LS, United Kingdom
| | - K. Rossi
- Physics Department, King’s College London, London WC2R 2LS, United Kingdom
| | - F. Baletto
- Physics Department, King’s College London, London WC2R 2LS, United Kingdom
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131
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Brault P, Neyts EC. Molecular dynamics simulations of supported metal nanocatalyst formation by plasma sputtering. Catal Today 2015. [DOI: 10.1016/j.cattod.2015.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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132
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Silva F, Galvão B, Voga G, Silva M, Rodrigues D, Belchior J. Exploring the MP2 energy surface of nanoalloy clusters with a genetic algorithm: Application to sodium–potassium. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.09.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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133
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Li L, Mo J, Li Z. Nanofluidic Diode for Simple Fluids without Moving Parts. PHYSICAL REVIEW LETTERS 2015; 115:134503. [PMID: 26451560 DOI: 10.1103/physrevlett.115.134503] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Indexed: 06/05/2023]
Abstract
The fabrication of small scale, fixed structure fluidic diodes for simple fluids is quite challenging and has not yet been achieved. Here, we fabricate a moving part-free nanofluidic diode for simple fluids using heterogeneous nanochannels, half of which is hydrophilic and the other half is hydrophobic. It accepts water flows in the forward (from hydrophilic to hydrophobic) direction, while the flows in the backward direction are blocked for pressure drop range 0<ΔP<0.63 MPa. The diode is ensured by a potential energy barrier at the channel entrance on the hydrophobic side due to the molecular interactions between the water and channel surface. As the upstream pressure becomes higher than 0.63 MPa, the fluidic diode turns to be a rectifier, which allows flows in both the forward and backward directions but with different flow rates. At sufficiently high driving pressures, the fluidic system fails in flow rectification, analogous to the breakdown of electronic diodes. The three different flow modes (diode, rectifier, and breakdown) of the fluidic chip and the underlying rectification mechanisms are confirmed by molecular dynamics simulations.
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Affiliation(s)
- Long Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jingwen Mo
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Zhigang Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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134
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Davis JBA, Shayeghi A, Horswell SL, Johnston RL. The Birmingham parallel genetic algorithm and its application to the direct DFT global optimisation of Ir(N) (N = 10-20) clusters. NANOSCALE 2015; 7:14032-8. [PMID: 26239404 DOI: 10.1039/c5nr03774c] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
A new open-source parallel genetic algorithm, the Birmingham parallel genetic algorithm, is introduced for the direct density functional theory global optimisation of metallic nanoparticles. The program utilises a pool genetic algorithm methodology for the efficient use of massively parallel computational resources. The scaling capability of the Birmingham parallel genetic algorithm is demonstrated through its application to the global optimisation of iridium clusters with 10 to 20 atoms, a catalytically important system with interesting size-specific effects. This is the first study of its type on Iridium clusters of this size and the parallel algorithm is shown to be capable of scaling beyond previous size restrictions and accurately characterising the structures of these larger system sizes. By globally optimising the system directly at the density functional level of theory, the code captures the cubic structures commonly found in sub-nanometre sized Ir clusters.
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Affiliation(s)
- Jack B A Davis
- School of Chemistry, University of Birmingham, Birmingham, B15 2TT, UK.
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135
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An alternative methodology to assess the quality of empirical potentials for small gold clusters. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.05.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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136
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Dufresne A, Ribeiro F, Tréglia G. How to derive tight-binding spd potentials? Application to zirconium. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:336301. [PMID: 26235825 DOI: 10.1088/0953-8984/27/33/336301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We propose here a general methodology to derive tight-binding potentials accounting for spd hybridization in transition metals, dealing simultaneously with electronic structure and energy properties. This methodology is illustrated for zirconium which is largely used for technological applications, in particular in the nuclear industry, and whose modelling is known to be complex and challenging. Such potentials are very promising. Their fits have a clear physical meaning with a limited amount of parameters and their complexity can be adjusted as a function of the problem under consideration.
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Affiliation(s)
- Alice Dufresne
- Centre Interdisciplinaire de Nanosciences de Marseille, CINaM, CNRS-Aix-Marseille Université, Campus de Luminy, Case 913, F13288 Marseille Cedex 9, France
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137
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Global optimization and oxygen dissociation on polyicosahedral Ag32Cu6 core-shell cluster for alkaline fuel cells. Sci Rep 2015; 5:11984. [PMID: 26148904 PMCID: PMC4493688 DOI: 10.1038/srep11984] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 06/11/2015] [Indexed: 11/08/2022] Open
Abstract
The structure of 38 atoms Ag-Cu cluster is studied by using a combination of a genetic algorithm global optimization technique and density functional theory (DFT) calculations. It is demonstrated that the truncated octahedral (TO) Ag32Cu6 core-shell cluster is less stable than the polyicosahedral (pIh) Ag32Cu6 core-shell cluster from the atomistic models and the DFT calculation shows an agreeable result, so the newfound pIh Ag32Cu6 core-shell cluster is further investigated for potential application for O2 dissociation in oxygen reduction reaction (ORR). The activation energy barrier for the O2 dissociation on pIh Ag32Cu6 core-shell cluster is 0.715 eV, where the d-band center is -3.395 eV and the density of states at the Fermi energy level is maximal for the favorable absorption site, indicating that the catalytic activity is attributed to a maximal charge transfer between an oxygen molecule and the pIh Ag32Cu6 core-shell cluster. This work revises the earlier idea that Ag32Cu6 core-shell nanoparticles are not suitable as ORR catalysts and confirms that Ag-Cu nanoalloy is a potential candidate to substitute noble Pt-based catalyst in alkaline fuel cells.
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138
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Simulation and experimental analysis of nanoindentation and mechanical properties of amorphous NiAl alloys. J Mol Model 2015; 21:161. [DOI: 10.1007/s00894-015-2714-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 05/19/2015] [Indexed: 10/23/2022]
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139
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Sun H, Ren Y, Wu Z, Xu N. Density functional calculation of the growth, electronic and bonding properties of titanium clusters Tin (n=2–20). COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.03.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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140
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Polukhin VA, Vatolin NA. Stability and thermal evolution of transition metal and silicon clusters. RUSSIAN CHEMICAL REVIEWS 2015. [DOI: 10.1070/rcr4411] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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141
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Peng L, Van Duyne RP, Marks LD. Strain-Induced Segregation in Bimetallic Multiply Twinned Particles. J Phys Chem Lett 2015; 6:1930-1934. [PMID: 26263272 DOI: 10.1021/acs.jpclett.5b00706] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We analyze the possibility of strain-induced segregation in bimetallic multiply twinned particles by an analytic first-order expansion within a continuum model. The results indicate that while the change in free energy may be small, there will be a noticeable segregation of larger atoms to the external surface and smaller ones to the core, which could have interesting effects when such nanoparticles are used as heterogeneous catalysts.
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Affiliation(s)
- Lingxuan Peng
- †Department of Materials Science and Engineering and ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Richard P Van Duyne
- †Department of Materials Science and Engineering and ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Laurence D Marks
- †Department of Materials Science and Engineering and ‡Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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142
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Thaler P, Volk A, Ratschek M, Koch M, Ernst WE. Molecular dynamics simulation of the deposition process of cold Ag-clusters under different landing conditions. J Chem Phys 2015; 140:044326. [PMID: 25669542 DOI: 10.1063/1.4862917] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a series of molecular dynamics simulations on the surface deposition process of initially free silver clusters (Agn) with different sizes (n = 100-2000) and morphologies. During the whole deposition process the morphology of the clusters was studied as a function of the landing conditions. These conditions include variations of the depth and range of the substrate potential as well as the thermal coupling to the surface and a variation of the impact velocity of the free clusters. Depending on the applied conditions the clusters' final form ranges from spread out fragments via deformed and restructured heaps to quasi unchanged spherical clusters sitting at the surface. Under certain landing conditions larger clusters retain their initial multiply twinned morphology upon deposition, while smaller ones undergo structural transitions to form single domain particles. Furthermore, the occurrence of a structural transition depends on the initial structure-initially decahedral clusters tend to conserve their morphology better than icosahedral ones. The same behavior can also be observed in our experiments, where silver clusters were grown in helium nanodroplets and subsequently deposited on amorphous carbon substrates.
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Affiliation(s)
- Philipp Thaler
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Alexander Volk
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Martin Ratschek
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Markus Koch
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Wolfgang E Ernst
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
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143
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Schebarchov D, Wales DJ. Quasi-combinatorial energy landscapes for nanoalloy structure optimisation. Phys Chem Chem Phys 2015; 17:28331-8. [PMID: 25970479 DOI: 10.1039/c5cp01198a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We formulate nanoalloy structure prediction as a mixed-variable optimisation problem, where the homotops can be associated with an effective, quasi-combinatorial energy landscape in permutation space. We survey this effective landscape for a representative set of binary systems modelled by the Gupta potential. In segregating systems with small lattice mismatch, we find that homotops have a relatively straightforward landscape with few local optima - a scenario well-suited for local (combinatorial) optimisation techniques that scale quadratically with system size. Combining these techniques with multiple local-neighbourhood structures yields a search for multiminima, and we demonstrate that generalised basin-hopping with a metropolis acceptance criterion in the space of multiminima can then be effective for global optimisation of binary and ternary nanoalloys.
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Affiliation(s)
- D Schebarchov
- University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW, UK.
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144
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Lei H, Li J, Luo J. Surface specific heats of metal nanocrystals at low temperatures. NANOSCALE 2015; 7:6762-6766. [PMID: 25805072 DOI: 10.1039/c5nr00056d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In order to quantitatively explain the enhanced specific heat of metal nanocrystals measured from 4.2 K to 80 K, an analytical expression has been deduced to determine the surface specific heat in nanocrystals, which is proportional to T(2.5) at low temperatures. The consequently calculated specific heat and surface Debye temperature of copper nanocrystals are in good agreement with the experimental data. This explains why the experimental specific heat of copper nanocrystals is enhanced with respect to the bulk and why it exhibits a different feature as a function of temperature from that of the bulk at low temperatures. The first experimental evidence is presented that the spatial dimension of surfaces should be neither pure 2D nor 3D, but between 2D and 3D, due to the effect of atoms in the core of the nanocrystals.
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Affiliation(s)
- Haile Lei
- Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-987, 621900 Mianyang, China.
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145
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Heard CJ, Johnston RL, Schön JC. Energy Landscape Exploration of Sub-Nanometre Copper-Silver Clusters. Chemphyschem 2015; 16:1461-9. [DOI: 10.1002/cphc.201402887] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Indexed: 11/12/2022]
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146
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Mo J, Li L, Zhou J, Xu D, Huang B, Li Z. Fluid infiltration pressure for hydrophobic nanochannels. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:033022. [PMID: 25871217 DOI: 10.1103/physreve.91.033022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Indexed: 06/04/2023]
Abstract
We investigate water infiltration pressure for hydrophobic nanochannels through molecular dynamics simulations. It is found that the entrance energy barrier significantly raises the infiltration pressure, which makes the classic Young-Laplace equation invalid for nanochannels. As the channel surface is tuned from superhydrophobic to hydrophobic, the infiltration pressure is greatly reduced mainly due to the decrease of the capillary pressure (Young-Laplace equation) caused by the contact angle change, while the contribution of the entrance energy barrier to the infiltration pressure, which is termed entrance barrier pressure, increases from 25% to 60%.
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Affiliation(s)
- Jingwen Mo
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Long Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jianfeng Zhou
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
- College of Mechanical and Power Engineering, Nanjing Tech University, Nanjing 211816, P.R. China
| | - Dongyan Xu
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
| | - Baoling Huang
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Zhigang Li
- Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
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147
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Ng MY, Ho IL, Chang YC. Crystallinity effects on scaling properties of photoinduced modes in silver nanoprisms. J Chem Phys 2015; 142:074707. [DOI: 10.1063/1.4908160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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148
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Baidyshev VS, Gafner YY, Samsonov VM, Bembel AG. Modeling possible structural transitions in aluminum and lead nanoclusters. CRYSTALLOGR REP+ 2015. [DOI: 10.1134/s1063774515010034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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149
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Sauceda HE, Garzón IL. Vibrational properties and specific heat of core–shell Ag–Au icosahedral nanoparticles. Phys Chem Chem Phys 2015; 17:28054-9. [DOI: 10.1039/c5cp00232j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The vibrational density of states (VDOS) of metal nanoparticles can be a fingerprint of their geometrical structure and determine their low-temperature thermal properties.
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Affiliation(s)
- Huziel E. Sauceda
- Instituto de Física
- Universidad Nacional Autónoma de México
- 01000 México, D. F
- Mexico
| | - Ignacio L. Garzón
- Instituto de Física
- Universidad Nacional Autónoma de México
- 01000 México, D. F
- Mexico
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150
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Arslan H, Garip AK, Johnston RL. Theoretical study of the structures and chemical ordering of cobalt–palladium nanoclusters. Phys Chem Chem Phys 2015; 17:28311-21. [DOI: 10.1039/c5cp01029b] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Global optimization of 1 : 1 compositions of (Co–Pd)N/2 up to N = 150 and all compositions of 34- and 38-atom binary clusters has been performed using a genetic algorithm, coupled with the Gupta empirical potential to model interatomic interactions.
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Affiliation(s)
- Haydar Arslan
- Bülent Ecevit University
- Department of Physics
- 67100 Zonguldak
- Turkey
| | - Ali Kemal Garip
- Bülent Ecevit University
- Department of Physics
- 67100 Zonguldak
- Turkey
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