K2Li2NiO4 crystallizes in the triclinic P1 space group. There are eight inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(4), and two equivalent O(8) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), and two equivalent O(12) atoms. In the third K site, K(3) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(4), one O(5), one O(6), and two equivalent O(14) atoms. In the fourth K site, K(4) is bonded in a 7-coordinate geometry to one O(11), one O(16), one O(3), one O(7), one O(8), and two equivalent O(1) atoms. In the fifth K site, K(5) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(16), one O(6), and one O(9) atom. In the sixth K site, K(6) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(13), one O(7), and two equivalent O(3) atoms. In the seventh K site, K(7) is bonded in a 6-coordinate geometry to one O(12), one O(13), one O(14), one O(15), and two equivalent O(5) atoms. In the eighth K site, K(8) is bonded in a 5-coordinate geometry to one O(13), one O(15), one O(7), and two equivalent O(9) atoms. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted rectangular see-saw-like geometry to one O(11), one O(3), one O(4), and one O(6) atom. In the second Li site, Li(2) is bonded to one O(11), one O(12), one O(4), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(4)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(6)O4 tetrahedra, and  an edgeedge with one Ni(3)O4 tetrahedra. In the third Li site, Li(3) is bonded to one O(13), one O(5), one O(6), and one O(9) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Ni(1)O4 tetrahedra,  a cornercorner with one Ni(2)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra, and  an edgeedge with one Ni(2)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to one O(11), one O(13), one O(14), and one O(6) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Ni(3)O4 tetrahedra. In the fifth Li site, Li(5) is bonded to one O(10), one O(15), one O(2), and one O(9) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra, corners with two equivalent Ni(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and  an edgeedge with one Li(7)O4 trigonal pyramid. In the sixth Li site, Li(6) is bonded to one O(12), one O(2), one O(7), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. In the seventh Li site, Li(7) is bonded to one O(10), one O(14), one O(15), and one O(16) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Li(4)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(5)O4 tetrahedra, and  an edgeedge with one Ni(4)O4 tetrahedra. In the eighth Li site, Li(8) is bonded in a 4-coordinate geometry to one O(13), one O(14), one O(16), and one O(6) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(7), and one O(9) atom to form distorted NiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra,  an edgeedge with one Li(5)O4 tetrahedra, and  an edgeedge with one Li(6)O4 tetrahedra. In the second Ni site, Ni(2) is bonded to one O(13), one O(3), one O(5), and one O(6) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. In the third Ni site, Ni(3) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(15), one O(16), and one O(8) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid, and  an edgeedge with one Li(7)O4 trigonal pyramid. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one K(1), one K(5), one K(6), two equivalent K(4), and one Ni(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), one K(2), one Li(5), one Li(6), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one K(2), one K(4), two equivalent K(6), one Li(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one K(1), one K(2), one K(3), one Li(1), one Li(2), and one Ni(3) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(2), one K(3), two equivalent K(7), one Li(3), and one Ni(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one K(3), one K(5), one Li(1), one Li(3), one Li(4), one Li(8), and one Ni(2) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one K(2), one K(4), one K(6), one K(8), one Li(6), and one Ni(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one K(4), two equivalent K(1), one Li(2), one Li(6), and one Ni(4) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one K(5), two equivalent K(8), one Li(3), one Li(5), and one Ni(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one K(1), one K(3), one K(5), one Li(5), one Li(7), and one Ni(4) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one K(4), one K(6), one Li(1), one Li(2), one Li(4), and one Ni(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one K(3), one K(7), two equivalent K(2), one Li(2), one Li(6), and one Ni(3) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one K(6), one K(7), one K(8), one Li(3), one Li(4), one Li(8), and one Ni(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one K(7), two equivalent K(3), one Li(4), one Li(7), one Li(8), and one Ni(3) atom. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to one K(7), one K(8), one Li(5), one Li(7), and one Ni(4) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to one K(4), one K(5), one Li(7), one Li(8), and one Ni(4) atom.
K2Li2NiO4 crystallizes in the triclinic P1 space group. There are eight inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(4), and two equivalent O(8) atoms. The K(1)-O(1) bond length is 2.97 Å. The K(1)-O(10) bond length is 2.90 Å. The K(1)-O(2) bond length is 2.78 Å. The K(1)-O(4) bond length is 2.79 Å. There is one shorter (2.77 Å) and one longer (2.91 Å) K(1)-O(8) bond length. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(7), and two equivalent O(12) atoms. The K(2)-O(2) bond length is 2.62 Å. The K(2)-O(3) bond length is 2.73 Å. The K(2)-O(4) bond length is 2.90 Å. The K(2)-O(5) bond length is 3.12 Å. The K(2)-O(7) bond length is 2.79 Å. There is one shorter (3.10 Å) and one longer (3.11 Å) K(2)-O(12) bond length. In the third K site, K(3) is bonded in a 7-coordinate geometry to one O(10), one O(12), one O(4), one O(5), one O(6), and two equivalent O(14) atoms. The K(3)-O(10) bond length is 2.76 Å. The K(3)-O(12) bond length is 3.22 Å. The K(3)-O(4) bond length is 2.80 Å. The K(3)-O(5) bond length is 2.90 Å. The K(3)-O(6) bond length is 3.11 Å. There is one shorter (2.94 Å) and one longer (2.97 Å) K(3)-O(14) bond length. In the fourth K site, K(4) is bonded in a 7-coordinate geometry to one O(11), one O(16), one O(3), one O(7), one O(8), and two equivalent O(1) atoms. The K(4)-O(11) bond length is 3.05 Å. The K(4)-O(16) bond length is 2.91 Å. The K(4)-O(3) bond length is 3.04 Å. The K(4)-O(7) bond length is 2.70 Å. The K(4)-O(8) bond length is 2.92 Å. There is one shorter (2.88 Å) and one longer (2.92 Å) K(4)-O(1) bond length. In the fifth K site, K(5) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(16), one O(6), and one O(9) atom. The K(5)-O(1) bond length is 2.59 Å. The K(5)-O(10) bond length is 2.66 Å. The K(5)-O(16) bond length is 2.85 Å. The K(5)-O(6) bond length is 2.67 Å. The K(5)-O(9) bond length is 2.72 Å. In the sixth K site, K(6) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(13), one O(7), and two equivalent O(3) atoms. The K(6)-O(1) bond length is 3.17 Å. The K(6)-O(11) bond length is 2.69 Å. The K(6)-O(13) bond length is 2.95 Å. The K(6)-O(7) bond length is 2.64 Å. There is one shorter (2.72 Å) and one longer (2.93 Å) K(6)-O(3) bond length. In the seventh K site, K(7) is bonded in a 6-coordinate geometry to one O(12), one O(13), one O(14), one O(15), and two equivalent O(5) atoms. The K(7)-O(12) bond length is 2.86 Å. The K(7)-O(13) bond length is 2.85 Å. The K(7)-O(14) bond length is 2.87 Å. The K(7)-O(15) bond length is 2.73 Å. There is one shorter (2.95 Å) and one longer (2.99 Å) K(7)-O(5) bond length. In the eighth K site, K(8) is bonded in a 5-coordinate geometry to one O(13), one O(15), one O(7), and two equivalent O(9) atoms. The K(8)-O(13) bond length is 3.08 Å. The K(8)-O(15) bond length is 2.61 Å. The K(8)-O(7) bond length is 2.82 Å. There is one shorter (2.75 Å) and one longer (2.83 Å) K(8)-O(9) bond length. There are eight inequivalent Li sites. In the first Li site, Li(1) is bonded in a distorted rectangular see-saw-like geometry to one O(11), one O(3), one O(4), and one O(6) atom. The Li(1)-O(11) bond length is 2.00 Å. The Li(1)-O(3) bond length is 2.00 Å. The Li(1)-O(4) bond length is 1.95 Å. The Li(1)-O(6) bond length is 2.09 Å. In the second Li site, Li(2) is bonded to one O(11), one O(12), one O(4), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(4)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(6)O4 tetrahedra, and  an edgeedge with one Ni(3)O4 tetrahedra. The Li(2)-O(11) bond length is 1.94 Å. The Li(2)-O(12) bond length is 2.03 Å. The Li(2)-O(4) bond length is 1.93 Å. The Li(2)-O(8) bond length is 1.96 Å. In the third Li site, Li(3) is bonded to one O(13), one O(5), one O(6), and one O(9) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Ni(1)O4 tetrahedra,  a cornercorner with one Ni(2)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra, and  an edgeedge with one Ni(2)O4 tetrahedra. The Li(3)-O(13) bond length is 2.00 Å. The Li(3)-O(5) bond length is 2.05 Å. The Li(3)-O(6) bond length is 2.12 Å. The Li(3)-O(9) bond length is 1.93 Å. In the fourth Li site, Li(4) is bonded to one O(11), one O(13), one O(14), and one O(6) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid,  an edgeedge with one Li(3)O4 tetrahedra, and  an edgeedge with one Ni(3)O4 tetrahedra. The Li(4)-O(11) bond length is 1.97 Å. The Li(4)-O(13) bond length is 2.00 Å. The Li(4)-O(14) bond length is 2.01 Å. The Li(4)-O(6) bond length is 1.96 Å. In the fifth Li site, Li(5) is bonded to one O(10), one O(15), one O(2), and one O(9) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra, corners with two equivalent Ni(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and  an edgeedge with one Li(7)O4 trigonal pyramid. The Li(5)-O(10) bond length is 1.94 Å. The Li(5)-O(15) bond length is 2.09 Å. The Li(5)-O(2) bond length is 1.93 Å. The Li(5)-O(9) bond length is 2.01 Å. In the sixth Li site, Li(6) is bonded to one O(12), one O(2), one O(7), and one O(8) atom to form distorted LiO4 tetrahedra that share  a cornercorner with one Li(5)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. The Li(6)-O(12) bond length is 2.07 Å. The Li(6)-O(2) bond length is 1.94 Å. The Li(6)-O(7) bond length is 1.97 Å. The Li(6)-O(8) bond length is 2.02 Å. In the seventh Li site, Li(7) is bonded to one O(10), one O(14), one O(15), and one O(16) atom to form distorted LiO4 trigonal pyramids that share  a cornercorner with one Li(4)O4 tetrahedra,  a cornercorner with one Ni(3)O4 tetrahedra,  a cornercorner with one Ni(4)O4 tetrahedra,  an edgeedge with one Li(5)O4 tetrahedra, and  an edgeedge with one Ni(4)O4 tetrahedra. The Li(7)-O(10) bond length is 2.00 Å. The Li(7)-O(14) bond length is 1.94 Å. The Li(7)-O(15) bond length is 1.92 Å. The Li(7)-O(16) bond length is 2.00 Å. In the eighth Li site, Li(8) is bonded in a 4-coordinate geometry to one O(13), one O(14), one O(16), and one O(6) atom. The Li(8)-O(13) bond length is 2.17 Å. The Li(8)-O(14) bond length is 2.03 Å. The Li(8)-O(16) bond length is 2.04 Å. The Li(8)-O(6) bond length is 1.96 Å. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(7), and one O(9) atom to form distorted NiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra,  an edgeedge with one Li(5)O4 tetrahedra, and  an edgeedge with one Li(6)O4 tetrahedra. The Ni(1)-O(1) bond length is 1.75 Å. The Ni(1)-O(2) bond length is 1.81 Å. The Ni(1)-O(7) bond length is 1.80 Å. The Ni(1)-O(9) bond length is 1.83 Å. In the second Ni site, Ni(2) is bonded to one O(13), one O(3), one O(5), and one O(6) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. The Ni(2)-O(13) bond length is 1.83 Å. The Ni(2)-O(3) bond length is 1.76 Å. The Ni(2)-O(5) bond length is 1.78 Å. The Ni(2)-O(6) bond length is 1.89 Å. In the third Ni site, Ni(3) is bonded to one O(11), one O(12), one O(14), and one O(4) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid,  an edgeedge with one Li(2)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. The Ni(3)-O(11) bond length is 1.87 Å. The Ni(3)-O(12) bond length is 1.85 Å. The Ni(3)-O(14) bond length is 1.89 Å. The Ni(3)-O(4) bond length is 1.80 Å. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(15), one O(16), and one O(8) atom to form NiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra,  a cornercorner with one Li(6)O4 tetrahedra, corners with two equivalent Li(5)O4 tetrahedra,  a cornercorner with one Li(7)O4 trigonal pyramid, and  an edgeedge with one Li(7)O4 trigonal pyramid. The Ni(4)-O(10) bond length is 1.83 Å. The Ni(4)-O(15) bond length is 1.80 Å. The Ni(4)-O(16) bond length is 1.87 Å. The Ni(4)-O(8) bond length is 1.81 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one K(1), one K(5), one K(6), two equivalent K(4), and one Ni(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), one K(2), one Li(5), one Li(6), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one K(2), one K(4), two equivalent K(6), one Li(1), and one Ni(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one K(1), one K(2), one K(3), one Li(1), one Li(2), and one Ni(3) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(2), one K(3), two equivalent K(7), one Li(3), and one Ni(2) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one K(3), one K(5), one Li(1), one Li(3), one Li(4), one Li(8), and one Ni(2) atom. In the seventh O site, O(7) is bonded in a 6-coordinate geometry to one K(2), one K(4), one K(6), one K(8), one Li(6), and one Ni(1) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one K(4), two equivalent K(1), one Li(2), one Li(6), and one Ni(4) atom. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one K(5), two equivalent K(8), one Li(3), one Li(5), and one Ni(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one K(1), one K(3), one K(5), one Li(5), one Li(7), and one Ni(4) atom. In the eleventh O site, O(11) is bonded in a 4-coordinate geometry to one K(4), one K(6), one Li(1), one Li(2), one Li(4), and one Ni(3) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one K(3), one K(7), two equivalent K(2), one Li(2), one Li(6), and one Ni(3) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one K(6), one K(7), one K(8), one Li(3), one Li(4), one Li(8), and one Ni(2) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one K(7), two equivalent K(3), one Li(4), one Li(7), one Li(8), and one Ni(3) atom. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to one K(7), one K(8), one Li(5), one Li(7), and one Ni(4) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to one K(4), one K(5), one Li(7), one Li(8), and one Ni(4) atom.