Materials Data on Li2Ti3CoO8 by Materials Project

Li2CoTi3O8 is Spinel-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three equivalent CoO6 octahedra and corners with nine TiO6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. There are a spread of Li–O bond distances ranging from 1.98–2.10 Å. In the second Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There is one shorter (1.79 Å) and three longer (1.94 Å) Li–O bond length. In the third Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There is one shorter (1.80 Å) and three longer (1.94 Å) Li–O bond length. In the fourth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with three equivalent CoO6 octahedra and corners with nine TiO6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. There are three shorter (1.99 Å) and one longer (2.10 Å) Li–O bond lengths. There are four inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with three LiO4 tetrahedra, an edgeedge with one CoO6 octahedra, and edges with four TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Ti–O bond distances ranging from 1.96–2.01 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with three LiO4 tetrahedra, an edgeedge with one CoO6 octahedra, and edges with four equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Ti–O bond distances ranging from 1.96–2.01 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with three LiO4 tetrahedra, an edgeedge with one CoO6 octahedra, and edges with four equivalent TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Ti–O bond distances ranging from 1.96–2.01 Å. In the fourth Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with three LiO4 tetrahedra, an edgeedge with one CoO6 octahedra, and edges with four TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Ti–O bond distances ranging from 1.96–2.01 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six TiO6 octahedra, corners with three equivalent LiO4 tetrahedra, and edges with three TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Co–O bond distances ranging from 2.11–2.22 Å. In the second Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six TiO6 octahedra, corners with three equivalent LiO4 tetrahedra, and edges with three TiO6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of Co–O bond distances ranging from 2.10–2.23 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two Ti4+, and one Co2+ atom. In the second O2- site, O2- is bonded to one Li1+, two equivalent Ti4+, and one Co2+ atom to form distorted OLiTi2Co tetrahedra that share corners with four OLiTi3 tetrahedra, a cornercorner with one OLiTi3 trigonal pyramid, edges with two equivalent OLiTi2Co tetrahedra, and an edgeedge with one OLiTi3 trigonal pyramid. In the third O2- site, O2- is bonded to one Li1+ and three Ti4+ atoms to form a mixture of distorted edge and corner-sharing OLiTi3 trigonal pyramids. In the fourth O2- site, O2- is bonded to one Li1+ and three Ti4+ atoms to form distorted OLiTi3 tetrahedra that share corners with six OLiTi2Co tetrahedra and corners with three equivalent OLiTi3 trigonal pyramids. In the fifth O2- site, O2- is bonded to one Li1+ and three Ti4+ atoms to form distorted OLiTi3 tetrahedra that share corners with six OLiTi2Co tetrahedra and corners with three equivalent OLiTi3 trigonal pyramids. In the sixth O2- site, O2- is bonded to one Li1+, two Ti4+, and one Co2+ atom to form distorted OLiTi2Co tetrahedra that share corners with four OLiTi2Co tetrahedra, a cornercorner with one OLiTi3 trigonal pyramid, edges with two OLiTi2Co tetrahedra, and an edgeedge with one OLiTi3 trigonal pyramid. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two equivalent Ti4+, and one Co2+ atom. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two equivalent Ti4+, and one Co2+ atom. In the ninth O2- site, O2- is bonded to one Li1+, two Ti4+, and one Co2+ atom to form distorted OLiTi2Co tetrahedra that share corners with four OLiTi2Co tetrahedra, a cornercorner with one OLiTi3 trigonal pyramid, edges with two OLiTi2Co tetrahedra, and an edgeedge with one OLiTi3 trigonal pyramid. In the tenth O2- site, O2- is bonded to one Li1+ and three Ti4+ atoms to form a mixture of distorted edge and corner-sharing OLiTi3 trigonal pyramids. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Li1+, two Ti4+, and one Co2+ atom. In the twelfth O2- site, O2- is bonded to one Li1+, two equivalent Ti4+, and one Co2+ atom to form distorted OLiTi2Co tetrahedra that share corners with four OLiTi2Co tetrahedra, a cornercorner with one OLiTi3 trigonal pyramid, edges with two equivalent OLiTi2Co tetrahedra, and an edgeedge with one OLiTi3 trigonal pyramid.

Li₂CoTi₃O₈为尖晶石衍生结构（Spinel-derived），结晶于单斜晶系Cm空间群（monoclinic Cm space group），其结构为三维网状结构。该结构中存在4个不等价的Li⁺位点：
在第一个Li⁺位点中，Li⁺与4个O²⁻原子配位，形成LiO₄四面体（LiO₄ tetrahedra），该四面体与3个等价的CoO₆八面体（CoO₆ octahedra）以及9个TiO₆八面体（TiO₆ octahedra）共顶点相连。共顶点八面体的倾斜角范围为57°~63°，Li-O键长分布在1.98~2.10 Å之间。
在第二个Li⁺位点中，Li⁺以畸变的矩形跷跷板状配位环境与4个O²⁻原子配位，存在1条较短的Li-O键（键长1.79 Å）与3条较长的Li-O键（键长1.94 Å）。
在第三个Li⁺位点中，Li⁺同样以畸变的矩形跷跷板状配位环境与4个O²⁻原子配位，存在1条较短的Li-O键（键长1.80 Å）与3条较长的Li-O键（键长1.94 Å）。
在第四个Li⁺位点中，Li⁺与4个O²⁻原子配位形成LiO₄四面体，该四面体与3个等价的CoO₆八面体以及9个TiO₆八面体共顶点相连。共顶点八面体的倾斜角范围为57°~63°，Li-O键长包含3条较短键（1.99 Å）与1条较长键（2.10 Å）。
该结构中存在4个不等价的Ti⁴+位点：
在第一个Ti⁴+位点中，Ti⁴+与6个O²⁻原子配位形成TiO₆八面体，该八面体与2个等价的CoO₆八面体共顶点、与3个LiO₄四面体共顶点，与1个CoO₆八面体共边，同时与4个TiO₆八面体共边。共顶点八面体的倾斜角为53°，Ti-O键长分布在1.96~2.01 Å之间。第二个至第四个Ti⁴+位点的配位环境与第一个Ti⁴+位点完全一致，Ti-O键长分布范围均为1.96~2.01 Å。
该结构中存在2个不等价的Co²+位点：
在第一个Co²+位点中，Co²+与6个O²⁻原子配位形成CoO₆八面体，该八面体与6个TiO₆八面体共顶点、与3个等价的LiO₄四面体共顶点，同时与3个TiO₆八面体共边。共顶点八面体的倾斜角为53°，Co-O键长分布在2.11~2.22 Å之间。
在第二个Co²+位点中，Co²+与6个O²⁻原子配位形成CoO₆八面体，该八面体与6个TiO₆八面体共顶点、与3个等价的LiO₄四面体共顶点，同时与3个TiO₆八面体共边。共顶点八面体的倾斜角为53°，Co-O键长分布在2.10~2.23 Å之间。
该结构中存在12个不等价的O²⁻位点：
1. 第一个O²⁻位点：O²⁻以畸变的矩形跷跷板状配位环境与1个Li⁺、2个Ti⁴+以及1个Co²+原子配位。
2. 第二个O²⁻位点：O²⁻与1个Li⁺、2个等价的Ti⁴+以及1个Co²+原子配位，形成畸变的OLiTi₂Co四面体，该四面体与4个OLiTi₃四面体共顶点、与1个OLiTi₃三角锥（trigonal pyramid）共顶点，与2个等价的OLiTi₂Co四面体共边，同时与1个OLiTi₃三角锥共边相连。
3. 第三个O²⁻位点：O²⁻与1个Li⁺和3个Ti⁴+原子配位，形成兼具畸变共边与共顶点特征的OLiTi₃三角锥。
4. 第四个O²⁻位点：O²⁻与1个Li⁺和3个Ti⁴+原子配位，形成畸变的OLiTi₃四面体，该四面体与6个OLiTi₂Co四面体共顶点，同时与3个等价的OLiTi₃三角锥共顶点。
5. 第五个O²⁻位点：其配位环境与第四个O²⁻位点完全一致。
6. 第六个O²⁻位点：O²⁻与1个Li⁺、2个Ti⁴+以及1个Co²+原子配位，形成畸变的OLiTi₂Co四面体，该四面体与4个OLiTi₂Co四面体共顶点、与1个OLiTi₃三角锥共顶点，与2个OLiTi₂Co四面体共边，同时与1个OLiTi₃三角锥共边相连。
7. 第七个O²⁻位点：O²⁻以畸变的矩形跷跷板状配位环境与1个Li⁺、2个等价的Ti⁴+以及1个Co²+原子配位。
8. 第八个O²⁻位点：其配位环境与第七个O²⁻位点完全一致。
9. 第九个O²⁻位点：其配位环境与第六个O²⁻位点完全一致。
10. 第十个O²⁻位点：其配位环境与第三个O²⁻位点完全一致。
11. 第十一个O²⁻位点：O²⁻以畸变的矩形跷跷板状配位环境与1个Li⁺、2个Ti⁴+以及1个Co²+原子配位。
12. 第十二个O²⁻位点：其配位环境与第二个O²⁻位点完全一致。