Journal ArticleDOI
Atomistic simulation of the structure and elastic properties of gold nanowires
Reads0
Chats0
TLDR
In this paper, the effect of free surfaces on the structure and elastic properties of gold nanowires aligned in the 〈1 0 0 ǫ and à −1 1 1ǫ crystallographic directions was studied.Abstract:
We performed atomistic simulations to study the effect of free surfaces on the structure and elastic properties of gold nanowires aligned in the 〈1 0 0〉 and 〈1 1 1〉 crystallographic directions. Computationally, we formed a nanowire by assembling gold atoms into a long wire with free sides by putting them in their bulk fcc lattice positions. We then performed a static relaxation on the assemblage. The tensile surface stresses on the sides of the wire cause the wire to contract along the length with respect to the original fcc lattice, and we characterize this deformation in terms of an equilibrium strain versus the cross-sectional area. While the surface stress causes wires of both orientations and all sizes to increasingly contract with decreasing cross-sectional area, when the cross-sectional area of a 〈1 0 0〉 nanowire is less than 1.83 nm ×1.83 nm , the wire undergoes a phase transformation from fcc to bct, and the equilibrium strain increases by an order of magnitude. We then applied a uniform uniaxial strain incrementally to 1.2% to the relaxed nanowires in a molecular statics framework. From the simulation results we computed the effective axial Young's modulus and Poisson's ratios of the nanowire as a function of cross-sectional area. We used two approaches to compute the effective elastic moduli, one based on a definition in terms of the strain derivative of the total energy and another in terms of the virial stress often used in atomistic simulations. Both give quantitatively similar results, showing an increase in Young's modulus with a decrease of cross-sectional area in the nanowires that do not undergo a phase transformation. Those that undergo a phase transformation experience an increase of about a factor of three of Young's modulus. The Poisson's ratio of the 〈1 0 0〉 wires that do not undergo a phase transformation show little change with the cross-sectional area. Those wires that undergo a phase transformation experience an increase of about 10% in Poisson's ratio. The 〈1 1 1〉 wires show, with a decrease of cross-sectional area, an increase in one of Poisson's ratios and small change in the other.read more
Citations
More filters
Journal ArticleDOI
Surface free energy and its effect on the elastic behavior of nano-sized particles, wires and films
TL;DR: In this paper, a framework is developed to incorporate the surface free energy into the continuum theory of mechanics, and it is demonstrated that the overall elastic behavior of structural elements (such as particles, wires, films) is size-dependent.
Journal ArticleDOI
Size-dependent effective elastic constants of solids containing nano-inhomogeneities with interface stress
TL;DR: In this article, the authors generalized the fundamental framework of micromechanical procedure to take into account the surface/interface stress effect at the nano-scale and applied it to the derivation of the effective moduli of solids containing nano-inhomogeneities.
Journal ArticleDOI
Surface Effect on the Elastic Behavior of Static Bending Nanowires
Jin He,Carmen M. Lilley +1 more
TL;DR: In this paper, the dependence of the surface effect on the overall Young's modulus of nanowires for three different boundary conditions: cantilever, simply supported, and fixed-fixed.
Journal ArticleDOI
Surface-chemistry-driven actuation in nanoporous gold
Jürgen Biener,Arne Wittstock,Arne Wittstock,Luis A. Zepeda-Ruiz,Monika M. Biener,Volkmar Zielasek,Denis Kramer,R. N. Viswanath,Jörg Weissmüller,Marcus Bäumer,A. V. Hamza +10 more
TL;DR: This work demonstrates that surface-chemistry-driven actuation can be realized in high-surface-area materials such as nanoporous gold, and achieves reversible strain amplitudes of the order of a few tenths of a per cent by alternating exposure of nanoporous Au to ozone and carbon monoxide.
Journal ArticleDOI
Nanomechanical resonators and their applications in biological/chemical detection: Nanomechanics principles
TL;DR: In this paper, the authors present a review of the physical properties of nanoresonator-based molecular detection at the nanoscale, focusing on issues of special relevance to the dynamic behavior of micro/nanoresonators and their applications in biological/chemical detection.
References
More filters
Journal ArticleDOI
Embedded-atom method: Derivation and application to impurities, surfaces, and other defects in metals
Murray S. Daw,Michael I. Baskes +1 more
TL;DR: In this paper, the authors derived an expression for the total energy of a metal using the embedding energy from which they obtained several ground-state properties, such as the lattice constant, elastic constants, sublimation energy, and vacancy-formation energy.
Journal ArticleDOI
Embedded-atom-method functions for the fcc metals Cu, Ag, Au, Ni, Pd, Pt, and their alloys.
TL;DR: A consistent set of embedding functions and pair interactions for use with the embedded-atom method was determined empirically by fitting to the sublimation energy, equilibrium lattice constant, elastic constants, and vacancy-formation energies of the pure metals and the heats of solution of the binary alloys as discussed by the authors.
MonographDOI
Mechanical Behavior of Materials
TL;DR: A balanced mechanics-materials approach and coverage of the latest developments in biomaterials and electronic materials, the new edition of this popular text is the most thorough and modern book available for upper-level undergraduate courses on the mechanical behavior of materials as discussed by the authors.
Journal ArticleDOI
Semiempirical, Quantum Mechanical Calculation of Hydrogen Embrittlement in Metals
Murray S. Daw,Michael I. Baskes +1 more
TL;DR: In this article, a semi-empirical model of metals and impurities (embedded atom method) was proposed to make possible a static treatment of the brittle fracture of a transition metal in the presence of hydrogen.
Journal ArticleDOI
Modified embedded-atom potentials for cubic materials and impurities
TL;DR: In a comprehensive study, the modified embedded-atom method is extended to a variety of cubic materials and impurities, including metals, semiconductors, and diatomic gases, all of which exhibit different types of bonding.
Related Papers (5)
Size-dependent elastic properties of nanosized structural elements
Ronald E. Miller,Vijay B. Shenoy +1 more