Superionic Conduction in Substoichiometric LiAl Alloy: An Ab Initio Study

被引：19

作者：

Cucinotta, Clotilde S. ^{[1
]}

Miceli, Giacomo ^{[1
]}

Raiteri, Paolo ^{[1
]}

Krack, Matthias ^{[1
]}

Kuehne, Thomas D. ^{[1
]}

Bernasconi, Marco ^{[2
]}

Parrinello, Michele ^{[1
]}

机构：

[1] Swiss Fed Inst Technol, Computat Sci Dept Chem & Appl Biosci, LUI, CH-6900 Lugano, Switzerland

[2] Univ Milano Bicocca, Dipartimento Sci Mat, I-20125 Milan, Italy

来源：

PHYSICAL REVIEW LETTERS | 2009年 / 103卷 / 12期

关键词：

SELF-DIFFUSION; NMR; PSEUDOPOTENTIALS;

D O I：

10.1103/PhysRevLett.103.125901

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Based on the new ab initio molecular dynamics method by Kuumlhne et al. [Phys. Rev. Lett. 98, 066401 (2007)], we studied the mechanism of superionic conduction in substoichiometric Li-poor Li(1+x)Al alloys by performing simulations at different temperatures for an overall simulation time of about 1 ns. The dynamical simulations revealed the microscopic path for the diffusion of Li vacancies. The calculated activation energy (0.11 eV) and the prefactor (D(0)=6.9x10(-4) cm(2)/s) for Li diffusivity via a vacancy-mediated mechanism are in good agreement with experimental NMR data. The calculation of the formation energies of different defects-Li and Al Frenkel pair and Li antisites-revealed that only Li(+) vacancies and Li(Al) antisites are present in the stability range of the Zintl phase -0.1 < x < 0.2.

引用

页数：4

共 23 条

[1] NMR-STUDY OF LI DIFFUSION IN BETA-LIAL [J].