β-LiFeO$_{2}$ Structure: AB_tI4_139_a_b-003
| Prototype | FeLiO$_{2}$ |
| AFLOW prototype label | AB_tI4_139_a_b-003 |
| ICSD | 28366 |
| Pearson symbol | tI4 |
| Space group number | 139 |
| Space group symbol | $I4/mmm$ |
| AFLOW prototype command |
aflow --proto=AB_tI4_139_a_b-003
--params=$a, \allowbreak c/a$ |
- FeLiO$_{2}$ exhibits a wide variety of structures, with the exact structure present depends on thermodynamic effects, preparation methods, and charge/discharge history.
- We follow the nomenclature of (Kanno, 1996), where appropriate, with modifications found in (Tabuchi, 1995) and (Abdel-Ghany, 2012). The following list of structures is no doubt incomplete:
- $\alpha$–LiFeO$_{2}$ is in the cubic rock salt ($B1$) structure, with lithium and iron randomly placed on the sodium site and oxygen on the chlorine site. It is synthesized at temperatures above 600°C.
- $\beta$–LiFeO$_{2}$ (this structure) is a tetragonal distortion of $\alpha$–LiFeO$_{2}$ with the lithium and iron atoms still randomly placed on their sublattice (we denote this site as Fe).
- $\beta'$–LiFeO$_{2}$ is monoclinic and transforms to $\gamma$–LiFeO$_{2}$ near room temperature. This is likely the phase (Kanno, 1996) refers to as $\beta$–LiFeO$_{2}$.
- $\gamma$–LiFeO$_{2}$ is created by low-temperature synthesis below 500°C and can be considered as an ordered version of $\alpha$–LiFeO$_{2}$, with a doubled unit cell.
- o-LiFeO$_{2}$ is orthorhombic, produced by an ion exchange interaction. It is (meta)-stable below 400°C, transforming to $\alpha$–LiFeO$_{2}$ above 600°C.
- In $\beta$–LiFeO$_{2}$ the iron and lithium atoms occupy the (1a) Wyckoff position equally (Anderson, 1964). We arbitrarily label these as iron here.
- (Anderson, 1964) place this in space group $I4/m$ #87, but the atomic positions are consistent with the higher symmetry $I4/mmm$ #139, so we place it there.
- $L'2_{0}$ FeC$_{x}$ and $\beta$–LiFeO$_{2}$ have the same AFLOW prototype label, AB_tI4_139_a_b. They are generated by the same symmetry operations with different sets of parameters (
--params) specified in their corresponding CIF files.
\[ \begin{array}{ccc}
\mathbf{a_{1}}&=&- \frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{2}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}- \frac{1}{2}a \,\mathbf{\hat{y}}+\frac{1}{2}c \,\mathbf{\hat{z}}\\\mathbf{a_{3}}&=&\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{1}{2}a \,\mathbf{\hat{y}}- \frac{1}{2}c \,\mathbf{\hat{z}}
\end{array}\]
Basis vectors
| Lattice coordinates | Cartesian coordinates | Wyckoff position | Atom type | |||
|---|---|---|---|---|---|---|
| $\mathbf{B_{1}}$ | = | $0$ | = | $0$ | (2a) | Fe I |
| $\mathbf{B_{2}}$ | = | $\frac{1}{2} \, \mathbf{a}_{1}+\frac{1}{2} \, \mathbf{a}_{2}$ | = | $\frac{1}{2}c \,\mathbf{\hat{z}}$ | (2b) | O I |
References
- J. C. Anderson and M. Schieber, Order-disorder transitions in heat-treated rock-salt Lithium Ferrite, J. Phys. Chem. Solids 25, 961–968 (1964), doi:10.1016/0022-3697(64)90033-2.
- R. Kanno, T. Shirane, Y. Kawamoto, Y. Takeda, M. Takano, M. Ohashi, and Y. Yamaguchi, Synthesis, Structure, and Electrochemical Properties of a New Lithium Iron Oxide, LiFeO$_{2}$, with a Corrugated Layer Structure, J. Electrochem. Soc. 143, 2435–2442 (1996), doi:10.1149/1.1837027.
- A. E. Abdel-Ghany, A. Mauger, H. Groult, K. Zaghib, and C. M. Julien, Structural properties and electrochemistry of α-LiFeO$_{2}$, J. Power Sources 197, 285–291 (2012), doi:10.1016/j.jpowsour.2011.09.054.
- Y. S. Lee, S. Sato, Y. K. Sun, K. Kobayakawa, and Y.Sato, A new type of orthorhombic LiFeO$_{2}$ with advanced battery performance and its structural change during cycling}, J. Power Sources \textbf{119-121, 285–289 (2003), doi:10.1016/S0378-7753(03)00152-6.
- M. Tabuchi, K. Ado, H. Sakaebe, C. Masquelier, H. Kageyama, and O. Nakamura, Preparation of AFeO$_{2}$ (A = Li, Na) by hydrothermal method, Solid State Ionics 79, 220–226 (1995), doi:10.1016/0167-2738(95)00065-E.
Found in
- M. Barré and M. Catti, Neutron diffraction study of the $\beta$' and $\gamma$ phases of LiFeO$_{2}$, J. Solid State Chem. 182, 2549–2554 (2009), doi:10.1016/j.jssc.2009.06.029.
Prototype Generator
aflow --proto=AB_tI4_139_a_b --params=$a,c/a$