Fe(AsO2)2 crystallizes in the tetragonal P4_2/mbc space group. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. As(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one As(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent As(1) atoms.
Fe(AsO2)2 crystallizes in the tetragonal P4_2/mbc space group. Fe(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form edge-sharing FeO6 octahedra. Both Fe(1)-O(2) bond lengths are 2.23 Å. All Fe(1)-O(1) bond lengths are 2.12 Å. As(1) is bonded in a distorted trigonal non-coplanar geometry to one O(1) and two equivalent O(2) atoms. The As(1)-O(1) bond length is 1.75 Å. Both As(1)-O(2) bond lengths are 1.89 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one As(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent As(1) atoms.