Na2Mo2O5 crystallizes in the orthorhombic Ima2 space group. Na(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(2), and four equivalent O(1) atoms. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MoO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra and corners with two equivalent Mo(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 17°. In the second Mo site, Mo(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form MoO4 tetrahedra that share corners with two equivalent Mo(1)O6 octahedra and corners with two equivalent Mo(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Mo(1) atoms to form distorted ONa4Mo2 octahedra that share corners with two equivalent O(1)Na4Mo2 octahedra, corners with four equivalent O(3)Na2Mo2 tetrahedra, edges with two equivalent O(1)Na4Mo2 octahedra, and faces with four equivalent O(1)Na4Mo2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Mo(1), and one Mo(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1) and two equivalent Mo(2) atoms to form distorted ONa2Mo2 tetrahedra that share corners with eight equivalent O(1)Na4Mo2 octahedra and corners with two equivalent O(3)Na2Mo2 tetrahedra. The corner-sharing octahedral tilt angles range from 21-86°.
Na2Mo2O5 crystallizes in the orthorhombic Ima2 space group. Na(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(2), and four equivalent O(1) atoms. The Na(1)-O(3) bond length is 2.40 Å. There is one shorter (2.33 Å) and one longer (2.66 Å) Na(1)-O(2) bond length. There are a spread of Na(1)-O(1) bond distances ranging from 2.43-2.71 Å. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MoO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra and corners with two equivalent Mo(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 17°. Both Mo(1)-O(2) bond lengths are 2.15 Å. All Mo(1)-O(1) bond lengths are 2.05 Å. In the second Mo site, Mo(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form MoO4 tetrahedra that share corners with two equivalent Mo(1)O6 octahedra and corners with two equivalent Mo(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. Both Mo(2)-O(2) bond lengths are 1.91 Å. There is one shorter (1.99 Å) and one longer (2.02 Å) Mo(2)-O(3) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Mo(1) atoms to form distorted ONa4Mo2 octahedra that share corners with two equivalent O(1)Na4Mo2 octahedra, corners with four equivalent O(3)Na2Mo2 tetrahedra, edges with two equivalent O(1)Na4Mo2 octahedra, and faces with four equivalent O(1)Na4Mo2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Mo(1), and one Mo(2) atom. In the third O site, O(3) is bonded to two equivalent Na(1) and two equivalent Mo(2) atoms to form distorted ONa2Mo2 tetrahedra that share corners with eight equivalent O(1)Na4Mo2 octahedra and corners with two equivalent O(3)Na2Mo2 tetrahedra. The corner-sharing octahedral tilt angles range from 21-86°.