THE EFFECT OF MIE-TYPE POTENTIAL RANGE ON THE COHESIVE ENERGY OF METALLIC NANOPARTICLES

2007 ◽  
Vol 06 (06) ◽  
pp. 461-466 ◽  
Author(s):  
T. BARAKAT ◽  
O. M. Al-DOSSARY ◽  
A. A. ALHARBI

We investigate the effect of Mie-type potential range on the cohesive energy of metallic nanoparticles using the size-dependent potential parameters method. The predicted cohesive energy for different cubic structures is observed to decrease with decreasing the particle size, and increase with decreasing the range of the interatomic potential, a result which is in the right direction at least to predict the experimental values of Molybdenum and Tungsten nanoparticles.

2014 ◽  
Vol 28 (19) ◽  
pp. 1450157 ◽  
Author(s):  
Kai-Tuo Huo ◽  
Xiao-Ming Chen

Size-dependent melting temperature of metallic nanoparticles is studied theoretically based on cohesive energy. Three factors are introduced in the present model. The k factor, i.e. efficiency of space filling of crystal lattice is defined as the ratio between the volume of the atoms in a crystal cell and that of the crystal cell. The β factor is defined as the ratio between the cohesive energy of surface atom and interior atom of a crystal. The qs factor represents the packing fraction on a surface crystalline plane. Considering the β, qs and k factors, the relationship between melting temperature and nanoparticle size is discussed. The obtained model is compared with the reported experimental data and the other models.


2020 ◽  
Author(s):  
◽  
Seyed Moein Rassoulinejad Mousavi

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI--COLUMBIA AT REQUEST OF AUTHOR.] A perfectly transferable interatomic potential that works for different materials and systems of interest is lacking. This work considers the transferability of several existing interatomic potentials by evaluating their capability at various temperatures, to determine the range of accuracy of these potentials in atomistic simulations. A series of embedded-atom-method (EAM) based interatomic potentials has been examined for precious and popular metals in nanoscale studies. The potentials have been obtained from various credible and trusted repositories and were compared to tackle the lack of a comparison between several existing models. The interatomic potentials designed for the single elements, binary, trinary and higher order compounds were tested for each species using molecular dynamics simulation. Validity of results arising from each potential was investigated against experimental values at different temperatures from a temperature range around Debye temperature to melting point. The data covers accuracy of all studied potentials for prediction of the single crystals' elastic stiffness constants as well as the bulk, shear and Young's modulus of the polycrystalline specimens. As testing and benchmarking results for users is a necessity before running a new simulation, results of this work increase their assurance and lead them to the right model by a way to easily look up data. Referring to this work also prevents any inaccurate prediction by an atomistic simulation due to use of an inappropriate interatomic potential.


2019 ◽  
Vol 9 (15) ◽  
pp. 3083
Author(s):  
Kai-Jian Huang ◽  
Shui-Jie Qin ◽  
Zheng-Ping Zhang ◽  
Zhao Ding ◽  
Zhong-Chen Bai

We develop a theoretical approach to investigate the impact that nonlocal and finite-size effects have on the dielectric response of plasmonic nanostructures. Through simulations, comprehensive comparisons of the electron energy loss spectroscopy (EELS) and the optical performance are discussed for a gold spherical dimer system in terms of different dielectric models. Our study offers a paradigm of high efficiency compatible dielectric theoretical framework for accounting the metallic nanoparticles behavior combining local, nonlocal and size-dependent effects in broader energy and size ranges. The results of accurate analysis and simulation for these effects unveil the weight and the evolution of both surface and bulk plasmons vibrational mechanisms, which are important for further understanding the electrodynamics properties of structures at the nanoscale. Particularly, our method can be extended to other plasmonic nanostructures where quantum-size or strongly interacting effects are likely to play an important role.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
C. A. Onate ◽  
T. A. Akanbi ◽  
I. B. Okon

AbstractAn approximate solution of the Schrӧdinger equation for a molecular attractive potential was obtained using the parametric Nikiforov–Uvarov method. The energy equation and the corresponding radial wave functions were calculated. The effects of the potential parameters on the energy eigenvalues were examined. The thermal properties under the molecular attractive potential were calculated and the behaviour of the thermal properties with the maximum quantum state (λ) and the temperature parameter (β) respectively, were studied. Using the molecular spectroscopic parameters, the Rydberg–Klein–Rees (RKR) of cesium dimer and lithium dimer were both obtained and compared with the experimental values. The RKR values of both cesium dimer and lithium dimer calculated aligned with the observed values. The deviation and average deviation of the RKR for each molecule were also calculated.


2021 ◽  
Vol 265 ◽  
pp. 107996
Author(s):  
José Diogo L. Dutra ◽  
Thiago D. Bispo ◽  
Sabrina M. de Freitas ◽  
Marcos V. dos S. Rezende

1980 ◽  
Vol 33 (2) ◽  
pp. 177 ◽  
Author(s):  
FC Barker

The nonresonant part of the 7Be(p, )I)8B cross section at low energies is recalculated by means of a direct-capture potential model, using parameter values determined by fitting 7Li(n, n)7Li and 7Li(n, )I)8Li data. Standard values of the potential parameters and spectroscopic factors give values of the 7Li(n,)I) cross section that are too large. Modified values that fit the thermal-neutron capture cross section predict 7Be(p,)I) cross sections that are much less than the experimental values. Also, shell model calculations predict resonant 7Be(p,)I) cross sections that are smaller than the experimental values. It is suggested that the accepted experimental values of the 7Be(p, )I) cross section may be too large, perhaps due partly to an overlarge accepted value for the 7Li(d, p)8Li cross section, which has been used for normalization purposes. A decrease in the 7Be(p,)I) cross section would reduce the calculated detection rate of solar neutrinos and lessen the discrepancy with the measured value.


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