NaLi2AsO4 crystallizes in the orthorhombic Pmn2_1 space group. Na(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. Li(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra and corners with four equivalent As(1)O4 tetrahedra. As(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AsO4 tetrahedra that share corners with eight equivalent Li(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Li(1), and one As(1) atom. In the second O site, O(2) is bonded to one Na(1), two equivalent Li(1), and one As(1) atom to form distorted corner-sharing ONaLi2As trigonal pyramids. In the third O site, O(3) is bonded to one Na(1), two equivalent Li(1), and one As(1) atom to form distorted corner-sharing ONaLi2As trigonal pyramids.
NaLi2AsO4 crystallizes in the orthorhombic Pmn2_1 space group. Na(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(3) atoms. The Na(1)-O(2) bond length is 2.40 Å. There is one shorter (2.38 Å) and one longer (2.84 Å) Na(1)-O(1) bond length. Both Na(1)-O(3) bond lengths are 2.29 Å. Li(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra and corners with four equivalent As(1)O4 tetrahedra. The Li(1)-O(1) bond length is 2.06 Å. The Li(1)-O(2) bond length is 2.01 Å. Both Li(1)-O(3) bond lengths are 1.99 Å. As(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AsO4 tetrahedra that share corners with eight equivalent Li(1)O4 tetrahedra. The As(1)-O(1) bond length is 1.73 Å. The As(1)-O(2) bond length is 1.73 Å. Both As(1)-O(3) bond lengths are 1.72 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Na(1), two equivalent Li(1), and one As(1) atom. In the second O site, O(2) is bonded to one Na(1), two equivalent Li(1), and one As(1) atom to form distorted corner-sharing ONaLi2As trigonal pyramids. In the third O site, O(3) is bonded to one Na(1), two equivalent Li(1), and one As(1) atom to form distorted corner-sharing ONaLi2As trigonal pyramids.