金属及相应纳米晶的空位形成能的计算.pdf

http//: Vacancy formation energies of elemental metals and corresponding nanoparticles D Xie *, M P Wang, L F Cao and W H Qi School of Materials Science and Engineering, Central South University, Changsha 4 10083, China * Author to whom correspondence should be addressed. E-mail: patriot_csu@ 163.com Abstract: A simplified but valid model for vacancy formation energies of elemental metals and corresponding nanoparticles is established. The predicted results on vacancy formation energies of the formulae for 57 A 1~A4 and sc elemental crystals are in agreement with most corresponding experimental values, semi-empirical results and first-principle calculations found in literatures. The predictions of size dependent vacancy formation energies of nanoparticles are discussed as well. Keywords: Modelling; Vacancy formation energy; Bonding; Metallic; Nanostructure 1. Introduction Vacancies in metals play very important role in the kinetic and thermodynamic properties of materials, and vacancy formation energy EV is a key concept in the understanding of processes that occur in metals during mechanical deformation or heat treatment [1]. During recent decades researchers have succeeded in determining EV of some metals from experiments such as DD (Differential dilatometry) measurement, PAS (Positron-annihilation spectroscopy) measurement, Δρ and Δρ q irr (Electric resistivity of quenched and irradiated samples) measurement etc. [2-5]; from 1