HfCrO3 crystallizes in the orthorhombic Pnma space group. Hf(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted HfO6 pentagonal pyramids that share corners with four equivalent Cr(1)O6 octahedra, corners with two equivalent Hf(1)O6 pentagonal pyramids, edges with four equivalent Cr(1)O6 octahedra, and edges with two equivalent Hf(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 54-80°. Cr(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted CrO6 octahedra that share corners with six equivalent Cr(1)O6 octahedra, corners with four equivalent Hf(1)O6 pentagonal pyramids, and edges with four equivalent Hf(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 55-58°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Hf(1) and two equivalent Cr(1) atoms. In the second O site, O(2) is bonded to two equivalent Hf(1) and two equivalent Cr(1) atoms to form a mixture of corner and edge-sharing OHf2Cr2 tetrahedra.
HfCrO3 crystallizes in the orthorhombic Pnma space group. Hf(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted HfO6 pentagonal pyramids that share corners with four equivalent Cr(1)O6 octahedra, corners with two equivalent Hf(1)O6 pentagonal pyramids, edges with four equivalent Cr(1)O6 octahedra, and edges with two equivalent Hf(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 54-80°. There is one shorter (2.00 Å) and one longer (2.06 Å) Hf(1)-O(1) bond length. There are two shorter (2.12 Å) and two longer (2.19 Å) Hf(1)-O(2) bond lengths. Cr(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted CrO6 octahedra that share corners with six equivalent Cr(1)O6 octahedra, corners with four equivalent Hf(1)O6 pentagonal pyramids, and edges with four equivalent Hf(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 55-58°. Both Cr(1)-O(1) bond lengths are 2.63 Å. There are two shorter (2.06 Å) and two longer (2.08 Å) Cr(1)-O(2) bond lengths. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Hf(1) and two equivalent Cr(1) atoms. In the second O site, O(2) is bonded to two equivalent Hf(1) and two equivalent Cr(1) atoms to form a mixture of corner and edge-sharing OHf2Cr2 tetrahedra.