Ca2NdTaO6 crystallizes in the monoclinic Pc space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CaO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-41°. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms. Nd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms. Ta(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share corners with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-41°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(2), one Nd(1), and one Ta(1) atom to form distorted corner-sharing OCa2NdTa tetrahedra. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), one Nd(1), and one Ta(1) atom to form distorted corner-sharing OCa2NdTa tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Nd(1), and one Ta(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), two equivalent Nd(1), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Nd(1), and one Ta(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), two equivalent Nd(1), and one Ta(1) atom.
Ca2NdTaO6 crystallizes in the monoclinic Pc space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CaO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-41°. The Ca(1)-O(1) bond length is 2.35 Å. The Ca(1)-O(2) bond length is 2.34 Å. The Ca(1)-O(3) bond length is 2.34 Å. The Ca(1)-O(4) bond length is 2.34 Å. The Ca(1)-O(5) bond length is 2.28 Å. The Ca(1)-O(6) bond length is 2.31 Å. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(4), one O(6), two equivalent O(3), and two equivalent O(5) atoms. The Ca(2)-O(1) bond length is 2.44 Å. The Ca(2)-O(2) bond length is 2.35 Å. The Ca(2)-O(4) bond length is 2.39 Å. The Ca(2)-O(6) bond length is 2.38 Å. There is one shorter (2.67 Å) and one longer (3.03 Å) Ca(2)-O(3) bond length. There is one shorter (2.79 Å) and one longer (2.84 Å) Ca(2)-O(5) bond length. Nd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms. The Nd(1)-O(1) bond length is 2.34 Å. The Nd(1)-O(2) bond length is 2.42 Å. The Nd(1)-O(3) bond length is 2.36 Å. The Nd(1)-O(5) bond length is 2.35 Å. There is one shorter (2.64 Å) and one longer (3.04 Å) Nd(1)-O(4) bond length. There is one shorter (2.77 Å) and one longer (2.83 Å) Nd(1)-O(6) bond length. Ta(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form TaO6 octahedra that share corners with six equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-41°. The Ta(1)-O(1) bond length is 2.04 Å. The Ta(1)-O(2) bond length is 2.01 Å. The Ta(1)-O(3) bond length is 2.03 Å. The Ta(1)-O(4) bond length is 2.03 Å. The Ta(1)-O(5) bond length is 2.00 Å. The Ta(1)-O(6) bond length is 2.00 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ca(2), one Nd(1), and one Ta(1) atom to form distorted corner-sharing OCa2NdTa tetrahedra. In the second O site, O(2) is bonded to one Ca(1), one Ca(2), one Nd(1), and one Ta(1) atom to form distorted corner-sharing OCa2NdTa tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Nd(1), and one Ta(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), two equivalent Nd(1), and one Ta(1) atom. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), one Nd(1), and one Ta(1) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(1), one Ca(2), two equivalent Nd(1), and one Ta(1) atom.