BaCO3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent O(1) atoms to form edge-sharing BaO8 hexagonal bipyramids. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to four equivalent O(1) and six equivalent O(2) atoms. C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(2) and one C(1) atom.
BaCO3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent O(1) atoms to form edge-sharing BaO8 hexagonal bipyramids. There are four shorter (2.72 Å) and four longer (2.97 Å) Ba(1)-O(1) bond lengths. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to four equivalent O(1) and six equivalent O(2) atoms. All Ba(2)-O(1) bond lengths are 2.99 Å. There are two shorter (2.64 Å) and four longer (3.06 Å) Ba(2)-O(2) bond lengths. C(1) is bonded in a trigonal planar geometry to one O(2) and two equivalent O(1) atoms. The C(1)-O(2) bond length is 1.29 Å. Both C(1)-O(1) bond lengths are 1.30 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Ba(2) and one C(1) atom.