MnMoO4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form MoO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 20-57°. In the second Mo site, Mo(2) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form MoO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-61°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mo(1)O4 tetrahedra, corners with four equivalent Mo(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mo(2)O4 tetrahedra, corners with four equivalent Mo(1)O4 tetrahedra, and edges with two equivalent Mn(1)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Mo(2) and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mo(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded to one Mo(2), one Mn(2), and two equivalent Mn(1) atoms to form distorted edge-sharing OMn3Mo tetrahedra. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mo(2) and one Mn(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Mo(1) and one Mn(2) atom.
MnMoO4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form MoO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra and corners with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 20-57°. Both Mo(1)-O(2) bond lengths are 1.81 Å. Both Mo(1)-O(5) bond lengths are 1.74 Å. In the second Mo site, Mo(2) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form MoO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra and corners with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 14-61°. The Mo(2)-O(3) bond length is 1.84 Å. The Mo(2)-O(4) bond length is 1.76 Å. Both Mo(2)-O(1) bond lengths are 1.74 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mo(1)O4 tetrahedra, corners with four equivalent Mo(2)O4 tetrahedra,  an edgeedge with one Mn(1)O6 octahedra, and edges with two equivalent Mn(2)O6 octahedra. Both Mn(1)-O(1) bond lengths are 2.07 Å. Both Mn(1)-O(2) bond lengths are 2.13 Å. Both Mn(1)-O(3) bond lengths are 2.25 Å. In the second Mn site, Mn(2) is bonded to one O(3), one O(4), two equivalent O(2), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mo(2)O4 tetrahedra, corners with four equivalent Mo(1)O4 tetrahedra, and edges with two equivalent Mn(1)O6 octahedra. The Mn(2)-O(3) bond length is 2.22 Å. The Mn(2)-O(4) bond length is 2.07 Å. Both Mn(2)-O(2) bond lengths are 2.19 Å. Both Mn(2)-O(5) bond lengths are 2.09 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Mo(2) and one Mn(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mo(1), one Mn(1), and one Mn(2) atom. In the third O site, O(3) is bonded to one Mo(2), one Mn(2), and two equivalent Mn(1) atoms to form distorted edge-sharing OMn3Mo tetrahedra. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Mo(2) and one Mn(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Mo(1) and one Mn(2) atom.