HoOOH is Ullmanite-like structured and crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of distorted edge and corner-sharing HoO6 octahedra. The corner-sharing octahedral tilt angles are 60°. H(1) is bonded in a single-bond geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Ho(1) and one H(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Ho(1) and one H(1) atom.
HoOOH is Ullmanite-like structured and crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of distorted edge and corner-sharing HoO6 octahedra. The corner-sharing octahedral tilt angles are 60°. There is one shorter (2.32 Å) and two longer (2.38 Å) Ho(1)-O(1) bond lengths. All Ho(1)-O(2) bond lengths are 2.19 Å. H(1) is bonded in a single-bond geometry to one O(1) and one O(2) atom. The H(1)-O(1) bond length is 0.99 Å. The H(1)-O(2) bond length is 1.75 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Ho(1) and one H(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Ho(1) and one H(1) atom.