The threshold displacement energies (TDEs) of lattice atoms in lithium ferrite (LiFe₅O₈) are calculated using first-principles molecular dynamics simulations. The TDEs vary with crystal direction and sublattice. The weighted average TDEs are 34.65, 28.54, 38.85, 37.92, and 34.31 eV for Fe^Tetra, Fe^Oct, Li, O^I, and O^II atoms in LiFe₅O₈, respectively. The Fe^Oct primary knock-on atom (PKA) has the smallest TDE. Various defects, including vacancies (${\mathrm{V}}_{\mathrm{F}{\mathrm{e}}^{\mathrm{Tetra}}}$, ${\mathrm{V}}_{\mathrm{F}{\mathrm{e}}^{\mathrm{Oct}}}$, ${\mathrm{V}}_{\mathrm{Li}}$, ${\mathrm{V}}_{{\mathrm{O}}^{\mathrm{I}}}$, and ${\mathrm{V}}_{{\mathrm{O}}^{\mathrm{II}}}$), interstitials (I_Fe, I_Li and I_O), antisite defects ($\mathrm{L}{\mathrm{i}}_{\mathrm{F}{\mathrm{e}}^{\mathrm{Oct}}}$, $\mathrm{L}{\mathrm{i}}_{\mathrm{F}{\mathrm{e}}^{\mathrm{Tetra}}}$ and $\mathrm{F}{\mathrm{e}}_{\mathrm{Li}}$), split interstitials (${\mathrm{D}}_{\mathrm{FeFe}}$, ${\mathrm{D}}_{\mathrm{LiLi}}$, ${\mathrm{D}}_{\mathrm{LiFe}}$, and ${\mathrm{D}}_{\mathrm{OO}}$), crowding defects (Crow_FeFeFe) and exchange defects (O_O), are formed by low-energy recoil events. The effect of the presence of these defects on the magnetic behavior in LFO is investigated using density functional theory. The occupation of the octahedral and tetrahedral sublattice in LiFe₅O₈ has an important effect on magnetization. The net magnetization decreases or increases when a Fe atom at an octahedral or tetrahedral site is replaced by a nonmagnetic atom, respectively. These results are helpful for using irradiation to tune the magnetic behavior of LiFe₅O₈ and applying magnetic devices based on LiFe₅O₈ in the presence of irradiation.

中文翻译：

---

LiFe5O8 阈位移能的第一性原理分子动力学研究

使用第一性原理分子动力学模拟计算铁酸锂 (LiFe ₅ O ₈ ) 中晶格原子的阈值位移能 (TDE) 。TDE 随晶体方向和亚晶格而变化。LiFe ₅ O _{8 中}Fe ^Tetra、Fe ^Oct、Li、O ^I和O ^II原子的加权平均TDE 分别为34.65、28.54、38.85、37.92 和34.31 eV 。Fe ^Oct初级碰撞原子 (PKA) 具有最小的 TDE。各种缺陷，包括空缺（${\mathrm{伏}}_{\mathrm{F}{\mathrm{电子}}^{\mathrm{利乐}}}$, ${\mathrm{伏}}_{\mathrm{F}{\mathrm{电子}}^{\mathrm{十月}}}$, ${\mathrm{伏}}_{李}$, ${\mathrm{伏}}_{{\mathrm{哦}}^{\mathrm{一世}}}$， 和 ${\mathrm{伏}}_{{\mathrm{哦}}^{二}}$）、间隙（I _Fe、I _Li和 I _O）、反位缺陷（$\mathrm{升}{\mathrm{一世}}_{\mathrm{F}{\mathrm{电子}}^{\mathrm{十月}}}$, $\mathrm{升}{\mathrm{一世}}_{\mathrm{F}{\mathrm{电子}}^{\mathrm{利乐}}}$ 和 $\mathrm{F}{\mathrm{电子}}_{李}$), 拆分插页式广告 (${\mathrm{D}}_{\mathrm{铁铁}}$, ${\mathrm{D}}_{\mathrm{李丽}}$, ${\mathrm{D}}_{\mathrm{生活}}$， 和 ${\mathrm{D}}_{\mathrm{面向对象}}$)、拥挤缺陷 (Crow _FeFeFe ) 和交换缺陷 (O _O ) 是由低能反冲事件形成的。使用密度泛函理论研究了这些缺陷的存在对 LFO 中磁行为的影响。LiFe ₅ O _{8 中}八面体和四面体亚晶格的占据对磁化强度有重要影响。当八面体或四面体位置的 Fe 原子分别被非磁性原子取代时，净磁化强度会降低或增加。这些结果有助于使用辐照来调整 LiFe ₅ O ₈的磁性行为和应用基于 LiFe ₅ O _{8 的}磁性装置 在辐照的情况下。