Li2Ni(CO3)2 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(12), one O(3), one O(4), and one O(5) atom. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted LiO5 square pyramids that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(11), one O(6), one O(7), one O(8), and one O(9) atom. In the fourth Li site, Li(4) is bonded to one O(1), one O(10), one O(11), and one O(9) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Ni(2)O6 octahedra and  a cornercorner with one Ni(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 20-25°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(12), one O(2), one O(4), and one O(8) atom to form distorted NiO5 trigonal bipyramids that share corners with two equivalent Li(2)O5 square pyramids and  a cornercorner with one Li(4)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to one O(10), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted NiO6 octahedra that share  a cornercorner with one Li(2)O5 square pyramid, corners with two equivalent Li(4)O4 tetrahedra, and  an edgeedge with one Li(2)O5 square pyramid. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(5) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(11), one O(7), and one O(8) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(10), one O(12), and one O(9) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(4), one Ni(1), and one C(1) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Li(2), one Ni(1), and one C(2) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Ni(2), and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Ni(1), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Li(1), one Ni(2), and one C(1) atom. In the sixth O site, O(6) is bonded to one Li(2), one Li(3), one Ni(2), and one C(2) atom to form distorted corner-sharing OLi2NiC tetrahedra. In the seventh O site, O(7) is bonded to one Li(2), one Li(3), one Ni(2), and one C(3) atom to form distorted corner-sharing OLi2NiC tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Ni(1), and one C(3) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(4), one Ni(2), and one C(4) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Li(4), one Ni(2), and one C(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Li(4), and one C(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one C(4) atom.
Li2Ni(CO3)2 crystallizes in the triclinic P1 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded in a 4-coordinate geometry to one O(12), one O(3), one O(4), and one O(5) atom. The Li(1)-O(12) bond length is 1.96 Å. The Li(1)-O(3) bond length is 1.93 Å. The Li(1)-O(4) bond length is 2.21 Å. The Li(1)-O(5) bond length is 1.98 Å. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form distorted LiO5 square pyramids that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(1)O5 trigonal bipyramids, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. The Li(2)-O(2) bond length is 2.16 Å. The Li(2)-O(3) bond length is 2.17 Å. The Li(2)-O(4) bond length is 2.03 Å. The Li(2)-O(6) bond length is 2.17 Å. The Li(2)-O(7) bond length is 2.02 Å. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(11), one O(6), one O(7), one O(8), and one O(9) atom. The Li(3)-O(11) bond length is 2.06 Å. The Li(3)-O(6) bond length is 2.02 Å. The Li(3)-O(7) bond length is 2.16 Å. The Li(3)-O(8) bond length is 2.06 Å. The Li(3)-O(9) bond length is 2.35 Å. In the fourth Li site, Li(4) is bonded to one O(1), one O(10), one O(11), and one O(9) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Ni(2)O6 octahedra and  a cornercorner with one Ni(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 20-25°. The Li(4)-O(1) bond length is 2.08 Å. The Li(4)-O(10) bond length is 1.95 Å. The Li(4)-O(11) bond length is 2.10 Å. The Li(4)-O(9) bond length is 1.95 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(12), one O(2), one O(4), and one O(8) atom to form distorted NiO5 trigonal bipyramids that share corners with two equivalent Li(2)O5 square pyramids and  a cornercorner with one Li(4)O4 tetrahedra. The Ni(1)-O(1) bond length is 2.06 Å. The Ni(1)-O(12) bond length is 2.05 Å. The Ni(1)-O(2) bond length is 2.09 Å. The Ni(1)-O(4) bond length is 2.13 Å. The Ni(1)-O(8) bond length is 2.01 Å. In the second Ni site, Ni(2) is bonded to one O(10), one O(3), one O(5), one O(6), one O(7), and one O(9) atom to form distorted NiO6 octahedra that share  a cornercorner with one Li(2)O5 square pyramid, corners with two equivalent Li(4)O4 tetrahedra, and  an edgeedge with one Li(2)O5 square pyramid. The Ni(2)-O(10) bond length is 2.08 Å. The Ni(2)-O(3) bond length is 2.18 Å. The Ni(2)-O(5) bond length is 2.08 Å. The Ni(2)-O(6) bond length is 2.16 Å. The Ni(2)-O(7) bond length is 2.08 Å. The Ni(2)-O(9) bond length is 2.11 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(3), and one O(5) atom. The C(1)-O(1) bond length is 1.30 Å. The C(1)-O(3) bond length is 1.30 Å. The C(1)-O(5) bond length is 1.30 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(2), one O(4), and one O(6) atom. The C(2)-O(2) bond length is 1.29 Å. The C(2)-O(4) bond length is 1.31 Å. The C(2)-O(6) bond length is 1.30 Å. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(11), one O(7), and one O(8) atom. The C(3)-O(11) bond length is 1.28 Å. The C(3)-O(7) bond length is 1.32 Å. The C(3)-O(8) bond length is 1.31 Å. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(10), one O(12), and one O(9) atom. The C(4)-O(10) bond length is 1.29 Å. The C(4)-O(12) bond length is 1.30 Å. The C(4)-O(9) bond length is 1.30 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(4), one Ni(1), and one C(1) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Li(2), one Ni(1), and one C(2) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Ni(2), and one C(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Li(2), one Ni(1), and one C(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Li(1), one Ni(2), and one C(1) atom. In the sixth O site, O(6) is bonded to one Li(2), one Li(3), one Ni(2), and one C(2) atom to form distorted corner-sharing OLi2NiC tetrahedra. In the seventh O site, O(7) is bonded to one Li(2), one Li(3), one Ni(2), and one C(3) atom to form distorted corner-sharing OLi2NiC tetrahedra. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Ni(1), and one C(3) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Li(3), one Li(4), one Ni(2), and one C(4) atom. In the tenth O site, O(10) is bonded in a distorted T-shaped geometry to one Li(4), one Ni(2), and one C(4) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Li(4), and one C(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one C(4) atom.