DOE OSTI2020
Tb5(RuO6)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded to seven O2- atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent TbO6 octahedra, corners with two equivalent RuO6 octahedra, a cornercorner with one TbO7 pentagonal bipyramid, edges with two equivalent RuO6 octahedra, and edges with six TbO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 43–56°. There are a spread of Tb–O bond distances ranging from 2.29–2.39 Å. In the second Tb3+ site, Tb3+ is bonded to seven O2- atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent TbO6 octahedra, a cornercorner with one TbO7 pentagonal bipyramid, an edgeedge with one TbO6 octahedra, edges with two equivalent RuO6 octahedra, and edges with six TbO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 54°. There are a spread of Tb–O bond distances ranging from 2.29–2.45 Å. In the third Tb3+ site, Tb3+ is bonded to six O2- atoms to form TbO6 octahedra that share corners with four equivalent RuO6 octahedra, corners with eight TbO7 pentagonal bipyramids, and edges with two equivalent TbO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. There are four shorter (2.33 Å) and two longer (2.41 Å) Tb–O bond lengths. Ru+4.50+ is bonded to six O2- atoms to form RuO6 octahedra that share corners with two equivalent TbO6 octahedra, corners with two equivalent TbO7 pentagonal bipyramids, edges with two equivalent RuO6 octahedra, and edges with four TbO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. There are four shorter (2.00 Å) and two longer (2.02 Å) Ru–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to four Tb3+ atoms to form OTb4 tetrahedra that share corners with ten OTb4 tetrahedra, corners with three equivalent OTb2Ru2 trigonal pyramids, and edges with four OTb4 tetrahedra. In the second O2- site, O2- is bonded to three Tb3+ and one Ru+4.50+ atom to form distorted OTb3Ru tetrahedra that share corners with ten OTb4 tetrahedra, a cornercorner with one OTb2Ru2 trigonal pyramid, edges with three OTb4 tetrahedra, and edges with two equivalent OTb2Ru2 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Tb3+ and two equivalent Ru+4.50+ atoms. In the fourth O2- site, O2- is bonded to two Tb3+ and two equivalent Ru+4.50+ atoms to form distorted OTb2Ru2 trigonal pyramids that share corners with eight OTb4 tetrahedra, edges with four equivalent OTb3Ru tetrahedra, and an edgeedge with one OTb2Ru2 trigonal pyramid.