On the mechanisms of ionic conductivity in BaLiF3: a molecular dynamics study.
On the mechanisms of ionic conductivity in BaLiF3: a molecular dynamics study.
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关于 BaLiF3 离子电导率的机制：分子动力学研究。
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
P. Heitjans
中科院分区：
文献类型：
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作者：
D. Zahn;S. Herrmann;P. Heitjans
使用分子模拟研究了BaLiF(3) 中离子电导率的机制。 （准）单晶超级电池模型的直接分子动力学模拟暗示了基于氟化物间隙（以及较小程度的 F(-) 空位）迁移的首选迁移机制。与之前的建模研究类似，理想BaLiF(3)晶体中与Frenkel缺陷形成相关的能量被发现为4-5 eV，这与实验观察到的离子电导率激活势垒仅为1 eV存在严重争议。然而，这一争议可以通过将 Ba(2+)↔ Li(+) 交换缺陷纳入其他单晶模型系统中来解决。事实上，在此类阳离子交换缺陷附近，F(-) 弗兰克尔缺陷形成能被确定为降低至 1.3 eV，而阳离子交换缺陷本身的形成能为 1.0 eV。因此，我们的模拟暗示了多种缺陷情况对于 BaLiF(3) 中离子电导率的重要性。
The mechanisms of ionic conductivity in BaLiF(3) are investigated using molecular simulations. Direct molecular dynamics simulations of (quasi) single crystalline super cell models hint at the preferred mobility mechanism which is based on fluoride interstitial (and to a smaller extent F(-) vacancy) migration. Analogous to previous modeling studies, the energy related to Frenkel defect formation in the ideal BaLiF(3) crystal was found as 4-5 eV which is in serious controversy to the experimentally observed activation barrier to ionic conductivity of only 1 eV. However, this controversy could be resolved by incorporating Ba(2+)↔ Li(+) exchange defects into the elsewise single crystalline model systems. Indeed, in the neighborhood of such cation exchange defects the F(-) Frenkel defect formation energy was identified to reduce to 1.3 eV whilst the cation exchange defect itself is related to a formation energy of 1.0 eV. Thus, our simulations hint at the importance of multiple defect scenarios for the ionic conductivity in BaLiF(3).
纳米级 CaF2/BaF2 异质层结构的分子动力学建模
影响因子：
3.7
作者：
D. Zahn;O. Hochrein;X. Guo;J. Maier
通讯作者：
J. Maier