HfNbO4 crystallizes in the monoclinic C2/c space group. Hf(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. Nb(1) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Hf(1) and two equivalent Nb(1) atoms to form a mixture of distorted edge and corner-sharing OHf2Nb2 tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Hf(1) and one Nb(1) atom.
HfNbO4 crystallizes in the monoclinic C2/c space group. Hf(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two shorter (2.17 Å) and two longer (2.35 Å) Hf(1)-O(1) bond lengths. There are two shorter (2.13 Å) and two longer (2.20 Å) Hf(1)-O(2) bond lengths. Nb(1) is bonded in a 6-coordinate geometry to two equivalent O(2) and four equivalent O(1) atoms. Both Nb(1)-O(2) bond lengths are 1.99 Å. There are two shorter (2.02 Å) and two longer (2.33 Å) Nb(1)-O(1) bond lengths. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Hf(1) and two equivalent Nb(1) atoms to form a mixture of distorted edge and corner-sharing OHf2Nb2 tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Hf(1) and one Nb(1) atom.