Materials Data on MgMn2O4 by Materials Project

MgMn2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine MnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–61°. There are three shorter (2.02 Å) and one longer (2.05 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.14 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four MnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.11 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.14 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are four shorter (2.07 Å) and two longer (2.11 Å) Mg–O bond lengths. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five MnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.11 Å. There are twelve inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.07 Å. In the second Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Mn–O bond distances ranging from 2.01–2.10 Å. In the third Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.98–2.07 Å. In the fourth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.07 Å. In the fifth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO4 tetrahedra, edges with two equivalent MnO6 octahedra, and edges with four MgO6 octahedra. There is two shorter (1.94 Å) and four longer (2.01 Å) Mn–O bond length. In the sixth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are two shorter (2.02 Å) and two longer (2.05 Å) Mn–O bond lengths. In the seventh Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO4 tetrahedra, edges with two equivalent MnO6 octahedra, and edges with four MgO6 octahedra. There is two shorter (1.94 Å) and four longer (2.01 Å) Mn–O bond length. In the eighth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.08 Å. In the ninth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are two shorter (2.02 Å) and two longer (2.05 Å) Mn–O bond lengths. In the tenth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.06 Å. In the eleventh Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Mn–O bond distances ranging from 2.01–2.10 Å. In the twelfth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine MnO6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. There are one shorter (2.04 Å) and three longer (2.05 Å) Mn–O bond lengths. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with two OMgMn3 tetrahedra, corners with two OMn4 trigonal pyramids, and edges with two OMgMn3 trigonal pyramids. In the second O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids. In the third O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with two OMgMn3 tetrahedra, corners with two OMn4 trigonal pyramids, and edges with two OMg2Mn2 trigonal pyramids. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the fifth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the ninth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the fifteenth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the sixteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the twentieth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the twenty-first O2- site, O2- is bonded to four Mn3+ atoms to form distorted OMn4 trigonal pyramids that share corners with two OMgMn3 tetrahedra, corners with two OMg2Mn2 trigonal pyramids, edges with two OMgMn3 tetrahedra, and an edgeedge with one OMgMn3 trigonal pyramid. In the twenty-second O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 tetrahedra that share a cornercorner with one OMgMn3 tetrahedra, corners with three OMn4 trigonal pyramids, an edgeedge with one OMgMn3 tetrahedra, and edges with two OMgMn3 trigonal pyramids. In the twenty-third O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with two OMg2Mn2 trigonal pyramids, edges with two OMgMn3 tetrahedra, and an edgeedge with one OMn4 trigonal pyramid. In the twenty-fourth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 tetrahedra that share a cornercorner with one OMgMn3 tetrahedra, corners with three OMn4 trigonal pyramids, an edgeedge with one OMgMn3 tetrahedra, and edges with two OMgMn3 trigonal pyramids.

四锰酸镁（MgMn₂O₄）具有类尖晶石结构，结晶于三斜晶系P1空间群（triclinic P1 space group），其晶体结构为三维网状。该体系存在6个不等价的Mg²+位点：
1. 首个Mg²+位点中，Mg²+与4个O²-配位形成MgO₄四面体，该四面体与3个MgO₆八面体和9个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为56°~61°，Mg-O键长包含3条较短的2.02 Å与1条较长的2.05 Å。
2. 第二个Mg²+位点中，Mg²+与6个O²-配位形成MgO₆八面体，该八面体与6个MnO₄四面体共享顶点，与2个MgO₆八面体和4个MnO₆八面体共享边，Mg-O键长分布范围为2.06~2.14 Å。
3. 第三个Mg²+位点中，Mg²+与6个O²-配位形成MgO₆八面体，该八面体与2个等价MgO₄四面体、4个MnO₄四面体共享顶点，与1个MgO₆八面体共享一条边，与5个MnO₆八面体共享边，Mg-O键长分布范围为2.06~2.11 Å。
4. 第四个Mg²+位点中，Mg²+与6个O²-配位形成MgO₆八面体，该八面体与6个MnO₄四面体共享顶点，与2个MgO₆八面体和4个MnO₆八面体共享边，Mg-O键长分布范围为2.06~2.14 Å。
5. 第五个Mg²+位点中，Mg²+与6个O²-配位形成MgO₆八面体，该八面体与6个MnO₄四面体共享顶点，与2个MgO₆八面体和4个MnO₆八面体共享边，Mg-O键长包含4条较短的2.07 Å与2条较长的2.11 Å。
6. 第六个Mg²+位点中，Mg²+与6个O²-配位形成MgO₆八面体，该八面体与1个MgO₄四面体、5个MnO₄四面体共享顶点，与1个MgO₆八面体共享一条边，与5个MnO₆八面体共享边，Mg-O键长分布范围为2.06~2.11 Å。

该体系存在12个不等价的Mn³+位点：
1. 首个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与2个等价MgO₄四面体、4个MnO₄四面体共享顶点，与3个MgO₆八面体和3个MnO₆八面体共享边，Mn-O键长分布范围为1.92~2.07 Å。
2. 第二个Mn³+位点中，Mn³+与4个O²-配位形成MnO₄四面体，该四面体与6个MgO₆八面体和6个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为58°~61°，Mn-O键长分布范围为2.01~2.10 Å。
3. 第三个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与3个等价MgO₄四面体、3个等价MnO₄四面体共享顶点，与2个MgO₆八面体和4个MnO₆八面体共享边，Mn-O键长分布范围为1.98~2.07 Å。
4. 第四个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与2个等价MgO₄四面体、4个MnO₄四面体共享顶点，与3个MgO₆八面体和3个MnO₆八面体共享边，Mn-O键长分布范围为1.92~2.07 Å。
5. 第五个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与6个MnO₄四面体共享顶点，与2个等价MnO₆八面体和4个MgO₆八面体共享边，Mn-O键长包含2条较短的1.94 Å与4条较长的2.01 Å。
6. 第六个Mn³+位点中，Mn³+与4个O²-配位形成MnO₄四面体，该四面体与6个MgO₆八面体和6个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为55°~63°，Mn-O键长包含2条较短的2.02 Å与2条较长的2.05 Å。
7. 第七个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与6个MnO₄四面体共享顶点，与2个等价MnO₆八面体和4个MgO₆八面体共享边，Mn-O键长包含2条较短的1.94 Å与4条较长的2.01 Å。
8. 第八个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与1个MgO₄四面体、5个MnO₄四面体共享顶点，与3个MgO₆八面体和3个MnO₆八面体共享边，Mn-O键长分布范围为1.92~2.08 Å。
9. 第九个Mn³+位点中，Mn³+与4个O²-配位形成MnO₄四面体，该四面体与6个MgO₆八面体和6个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为56°~62°，Mn-O键长包含2条较短的2.02 Å与2条较长的2.05 Å。
10. 第十个Mn³+位点中，Mn³+与6个O²-配位形成MnO₆八面体，该八面体与1个MgO₄四面体、5个MnO₄四面体共享顶点，与3个MgO₆八面体和3个MnO₆八面体共享边，Mn-O键长分布范围为1.92~2.06 Å。
11. 第十一个Mn³+位点中，Mn³+与4个O²-配位形成MnO₄四面体，该四面体与6个MgO₆八面体和6个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为58°~61°，Mn-O键长分布范围为2.01~2.10 Å。
12. 第十二个Mn³+位点中，Mn³+与4个O²-配位形成MnO₄四面体，该四面体与3个MgO₆八面体和9个MnO₆八面体共享顶点，共顶点八面体的倾斜角范围为57°~63°，Mn-O键长包含1条较短的2.04 Å与3条较长的2.05 Å。

该体系存在24个不等价的O²-位点：
1. 首个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成畸变的OMg₂Mn₂三角锥（trigonal pyramid），该三角锥与2个OMgMn₃四面体共享顶点，与2个OMn₄三角锥共享顶点，与2个OMgMn₃三角锥共享边。
2. 第二个O²-位点中，O²-与1个Mg²+和3个Mn³+配位，形成兼具畸变边共享与顶点共享特征的OMgMn₃三角锥。
3. 第三个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成畸变的OMg₂Mn₂三角锥，该三角锥与2个OMgMn₃四面体共享顶点，与2个OMn₄三角锥共享顶点，与2个OMg₂Mn₂三角锥共享边。
4. 第四个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
5. 第五个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成兼具畸变边共享与顶点共享特征的OMg₂Mn₂三角锥。
6. 第六个O²-位点中，O²-采取矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
7. 第七个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
8. 第八个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与2个Mg²+和2个Mn³+配位。
9. 第九个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成兼具畸变边共享与顶点共享特征的OMg₂Mn₂三角锥。
10. 第十个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
11. 第十一个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
12. 第十二个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与2个Mg²+和2个Mn³+配位。
13. 第十三个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与2个Mg²+和2个Mn³+配位。
14. 第十四个O²-位点中，O²-采取矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
15. 第十五个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成兼具畸变边共享与顶点共享特征的OMg₂Mn₂三角锥。
16. 第十六个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与2个Mg²+和2个Mn³+配位。
17. 第十七个O²-位点中，O²-采取矩形跷跷板状配位构型，与2个Mg²+和2个Mn³+配位。
18. 第十八个O²-位点中，O²-采取畸变矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
19. 第十九个O²-位点中，O²-采取矩形跷跷板状配位构型，与1个Mg²+和3个Mn³+配位。
20. 第二十个O²-位点中，O²-与2个Mg²+和2个Mn³+配位，形成兼具畸变边共享与顶点共享特征的OMg₂Mn₂三角锥。
21. 第二十一个O²-位点中，O²-与4个Mn³+配位，形成畸变的OMn₄三角锥，该三角锥与2个OMgMn₃四面体共享顶点，与2个OMg₂Mn₂三角锥共享顶点，与2个OMgMn₃四面体共享边，与1个OMgMn₃三角锥共享一条边。
22. 第二十二个O²-位点中，O²-与1个Mg²+和3个Mn³+配位，形成畸变的OMgMn₃四面体，该四面体与1个OMgMn₃四面体共享顶点，与3个OMn₄三角锥共享顶点，与1个OMgMn₃四面体共享一条边，与2个OMgMn₃三角锥共享边。
23. 第二十三个O²-位点中，O²-与1个Mg²+和3个Mn³+配位，形成畸变的OMgMn₃三角锥，该三角锥与2个OMg₂Mn₂三角锥共享顶点，与2个OMgMn₃四面体共享边，与1个OMn₄三角锥共享一条边。
24. 第二十四个O²-位点中，O²-与1个Mg²+和3个Mn³+配位，形成畸变的OMgMn₃四面体，该四面体与1个OMgMn₃四面体共享顶点，与3个OMn₄三角锥共享顶点，与1个OMgMn₃四面体共享一条边，与2个OMgMn₃三角锥共享边。