Na2MnNiO4 is Caswellsilverite-derived structured and crystallizes in the trigonal R-3m space group. Na(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-13°. Mn(1) is bonded to six equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. Ni(1) is bonded to six equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 10°. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Na(1) and three equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share corners with three equivalent O(2)Na3Mn3 octahedra, corners with three equivalent O(1)Na3Ni3 octahedra, edges with three equivalent O(2)Na3Mn3 octahedra, and edges with nine equivalent O(1)Na3Ni3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second O site, O(2) is bonded to three equivalent Na(1) and three equivalent Mn(1) atoms to form ONa3Mn3 octahedra that share corners with three equivalent O(2)Na3Mn3 octahedra, corners with three equivalent O(1)Na3Ni3 octahedra, edges with three equivalent O(1)Na3Ni3 octahedra, and edges with nine equivalent O(2)Na3Mn3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°.
Na2MnNiO4 is Caswellsilverite-derived structured and crystallizes in the trigonal R-3m space group. Na(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted NaO6 octahedra that share corners with three equivalent Mn(1)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with six equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-13°. All Na(1)-O(1) bond lengths are 2.33 Å. All Na(1)-O(2) bond lengths are 2.47 Å. Mn(1) is bonded to six equivalent O(2) atoms to form MnO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 13°. All Mn(1)-O(2) bond lengths are 2.06 Å. Ni(1) is bonded to six equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent Na(1)O6 octahedra, edges with six equivalent Na(1)O6 octahedra, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 10°. All Ni(1)-O(1) bond lengths are 2.05 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Na(1) and three equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share corners with three equivalent O(2)Na3Mn3 octahedra, corners with three equivalent O(1)Na3Ni3 octahedra, edges with three equivalent O(2)Na3Mn3 octahedra, and edges with nine equivalent O(1)Na3Ni3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second O site, O(2) is bonded to three equivalent Na(1) and three equivalent Mn(1) atoms to form ONa3Mn3 octahedra that share corners with three equivalent O(2)Na3Mn3 octahedra, corners with three equivalent O(1)Na3Ni3 octahedra, edges with three equivalent O(1)Na3Ni3 octahedra, and edges with nine equivalent O(2)Na3Mn3 octahedra. The corner-sharing octahedral tilt angles range from 0-4°.