Li5NiSi2O8 is beta beryllia-derived structured and crystallizes in the monoclinic C2 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. In the third Li site, Li(3) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. Ni(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with two equivalent O(2)Li3Si tetrahedra, corners with four equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(4)Li3Si tetrahedra, and  an edgeedge with one O(1)Li2SiNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(3), one Li(4), and one Si(1) atom to form distorted OLi3Si tetrahedra that share corners with two equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(4)Li3Si tetrahedra, and  an edgeedge with one O(2)Li3Si tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(3), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with two equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(2)Li3Si tetrahedra, and  an edgeedge with one O(4)Li3Si tetrahedra. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Li(4), and one Si(1) atom to form OLi3Si tetrahedra that share corners with two equivalent O(4)Li3Si tetrahedra, corners with four equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(2)Li3Si tetrahedra, and  an edgeedge with one O(3)Li2SiNi tetrahedra.
Li5NiSi2O8 is beta beryllia-derived structured and crystallizes in the monoclinic C2 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with two equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Si(1)O4 tetrahedra. The Li(1)-O(1) bond length is 2.05 Å. The Li(1)-O(2) bond length is 1.92 Å. The Li(1)-O(3) bond length is 2.23 Å. The Li(1)-O(4) bond length is 1.97 Å. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(4)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. Both Li(2)-O(1) bond lengths are 2.05 Å. Both Li(2)-O(4) bond lengths are 1.89 Å. In the third Li site, Li(3) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(4)O4 tetrahedra. Both Li(3)-O(2) bond lengths are 1.96 Å. Both Li(3)-O(3) bond lengths are 2.01 Å. In the fourth Li site, Li(4) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(3)O4 tetrahedra. Both Li(4)-O(2) bond lengths are 1.99 Å. Both Li(4)-O(4) bond lengths are 1.93 Å. Ni(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Li(2)O4 tetrahedra. Both Ni(1)-O(1) bond lengths are 1.90 Å. Both Ni(1)-O(3) bond lengths are 1.84 Å. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, and  an edgeedge with one Li(1)O4 tetrahedra. The Si(1)-O(1) bond length is 1.68 Å. The Si(1)-O(2) bond length is 1.61 Å. The Si(1)-O(3) bond length is 1.70 Å. The Si(1)-O(4) bond length is 1.61 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with two equivalent O(2)Li3Si tetrahedra, corners with four equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(4)Li3Si tetrahedra, and  an edgeedge with one O(1)Li2SiNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(3), one Li(4), and one Si(1) atom to form distorted OLi3Si tetrahedra that share corners with two equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(4)Li3Si tetrahedra, and  an edgeedge with one O(2)Li3Si tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(3), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with two equivalent O(3)Li2SiNi tetrahedra, corners with four equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(2)Li3Si tetrahedra, and  an edgeedge with one O(4)Li3Si tetrahedra. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Li(4), and one Si(1) atom to form OLi3Si tetrahedra that share corners with two equivalent O(4)Li3Si tetrahedra, corners with four equivalent O(1)Li2SiNi tetrahedra, corners with four equivalent O(2)Li3Si tetrahedra, and  an edgeedge with one O(3)Li2SiNi tetrahedra.