Materials Data on Tb2Nb2O7 by Materials Project
Tb2Nb2O7 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.25 Å) and six longer (2.45 Å) Tb–O bond lengths. Nb4+ is bonded to six equivalent O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Nb–O bond lengths are 2.09 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Tb3+ and two equivalent Nb4+ atoms to form a mixture of distorted edge and corner-sharing OTb2Nb2 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Tb3+ atoms to form a mixture of edge and corner-sharing OTb4 tetrahedra.