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 to one O(11), one O(2), one O(4), and one O(6) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-79°. In the second Li site, Li(2) is bonded to one O(1), one O(3), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-78°. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(12), one O(3), one O(5), one O(8), and one O(9) atom. In the fourth Li site, Li(4) is bonded in a 4-coordinate geometry to one O(10), one O(11), one O(2), and one O(7) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(11), one O(12), one O(2), and one O(4) atom to form NiO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. 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(2), and one O(3) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(10), 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(11), 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(2), one Ni(2), and one C(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(4), one Ni(2), and one C(1) atom to form a mixture of distorted corner and edge-sharing OLi2NiC trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Ni(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Ni(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Ni(1), and one C(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one C(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Li(4), one Ni(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal pyramidal geometry to one Li(2), one Li(3), one Ni(1), and one C(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Ni(1), and one C(4) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(4), one Ni(2), and one C(3) atom. In the eleventh O site, O(11) is bonded to one Li(1), one Li(4), one Ni(2), and one C(4) atom to form a mixture of distorted corner and edge-sharing OLi2NiC trigonal pyramids. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(3), one Ni(2), 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 to one O(11), one O(2), one O(4), and one O(6) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-79°. The Li(1)-O(11) bond length is 2.21 Å. The Li(1)-O(2) bond length is 2.04 Å. The Li(1)-O(4) bond length is 2.00 Å. The Li(1)-O(6) bond length is 1.96 Å. In the second Li site, Li(2) is bonded to one O(1), one O(3), one O(5), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-78°. The Li(2)-O(1) bond length is 1.97 Å. The Li(2)-O(3) bond length is 2.02 Å. The Li(2)-O(5) bond length is 2.01 Å. The Li(2)-O(8) bond length is 2.18 Å. In the third Li site, Li(3) is bonded in a 5-coordinate geometry to one O(12), one O(3), one O(5), one O(8), and one O(9) atom. The Li(3)-O(12) bond length is 1.97 Å. The Li(3)-O(3) bond length is 2.60 Å. The Li(3)-O(5) bond length is 2.46 Å. The Li(3)-O(8) bond length is 2.08 Å. The Li(3)-O(9) bond length is 1.99 Å. In the fourth Li site, Li(4) is bonded in a 4-coordinate geometry to one O(10), one O(11), one O(2), and one O(7) atom. The Li(4)-O(10) bond length is 2.00 Å. The Li(4)-O(11) bond length is 2.04 Å. The Li(4)-O(2) bond length is 2.25 Å. The Li(4)-O(7) bond length is 1.98 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. The Ni(1)-O(3) bond length is 2.09 Å. The Ni(1)-O(5) bond length is 2.09 Å. The Ni(1)-O(6) bond length is 2.10 Å. The Ni(1)-O(7) bond length is 2.11 Å. The Ni(1)-O(8) bond length is 2.10 Å. The Ni(1)-O(9) bond length is 2.07 Å. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(11), one O(12), one O(2), and one O(4) atom to form NiO6 octahedra that share  a cornercorner with one Li(1)O4 tetrahedra,  a cornercorner with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. The Ni(2)-O(1) bond length is 2.11 Å. The Ni(2)-O(10) bond length is 2.07 Å. The Ni(2)-O(11) bond length is 2.10 Å. The Ni(2)-O(12) bond length is 2.11 Å. The Ni(2)-O(2) bond length is 2.10 Å. The Ni(2)-O(4) bond length is 2.07 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(2), and one O(3) atom. The C(1)-O(1) bond length is 1.30 Å. The C(1)-O(2) bond length is 1.31 Å. The C(1)-O(3) bond length is 1.29 Å. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. The C(2)-O(4) bond length is 1.29 Å. The C(2)-O(5) 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(10), one O(7), and one O(8) atom. The C(3)-O(10) bond length is 1.29 Å. The C(3)-O(7) bond length is 1.30 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(11), one O(12), and one O(9) atom. The C(4)-O(11) bond length is 1.31 Å. The C(4)-O(12) bond length is 1.30 Å. The C(4)-O(9) bond length is 1.29 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Li(2), one Ni(2), and one C(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(4), one Ni(2), and one C(1) atom to form a mixture of distorted corner and edge-sharing OLi2NiC trigonal pyramids. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Ni(1), and one C(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Li(1), one Ni(2), and one C(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Li(2), one Li(3), one Ni(1), and one C(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one C(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Li(4), one Ni(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal pyramidal geometry to one Li(2), one Li(3), one Ni(1), and one C(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal non-coplanar geometry to one Li(3), one Ni(1), and one C(4) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Li(4), one Ni(2), and one C(3) atom. In the eleventh O site, O(11) is bonded to one Li(1), one Li(4), one Ni(2), and one C(4) atom to form a mixture of distorted corner and edge-sharing OLi2NiC trigonal pyramids. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Li(3), one Ni(2), and one C(4) atom.