NaLiH8(CO2)4 crystallizes in the monoclinic C2/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(6), and two equivalent O(7) atoms. Both Na(1)-O(1) bond lengths are 2.34 Å. Both Na(1)-O(6) bond lengths are 2.41 Å. Both Na(1)-O(7) bond lengths are 2.67 Å. In the second Na site, Na(2) is bonded to two equivalent O(6), two equivalent O(7), and two equivalent O(8) atoms to form NaO6 octahedra that share edges with two equivalent Li(1)O5 square pyramids. Both Na(2)-O(6) bond lengths are 2.40 Å. Both Na(2)-O(7) bond lengths are 2.45 Å. Both Na(2)-O(8) bond lengths are 2.44 Å. Li(1) is bonded to one O(1), one O(3), one O(4), one O(6), and one O(8) atom to form distorted LiO5 square pyramids that share  an edgeedge with one Na(2)O6 octahedra. The Li(1)-O(1) bond length is 1.96 Å. The Li(1)-O(3) bond length is 2.00 Å. The Li(1)-O(4) bond length is 2.02 Å. The Li(1)-O(6) bond length is 2.33 Å. The Li(1)-O(8) bond length is 2.04 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a distorted bent 120 degrees geometry to one O(1) and one O(2) atom. The C(1)-O(1) bond length is 1.26 Å. The C(1)-O(2) bond length is 1.28 Å. In the second C site, C(2) is bonded in a distorted water-like geometry to one H(1) and one O(3) atom. The C(2)-H(1) bond length is 1.10 Å. The C(2)-O(3) bond length is 1.42 Å. In the third C site, C(3) is bonded in a distorted water-like geometry to one H(2) and one O(4) atom. The C(3)-H(2) bond length is 1.10 Å. The C(3)-O(4) bond length is 1.43 Å. In the fourth C site, C(4) is bonded in a distorted bent 120 degrees geometry to one O(5) and one O(6) atom. The C(4)-O(5) bond length is 1.27 Å. The C(4)-O(6) bond length is 1.26 Å. There are eight inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one C(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one C(3) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to one O(5) and one O(7) atom. The H(3)-O(5) bond length is 1.67 Å. The H(3)-O(7) bond length is 1.00 Å. In the fourth H site, H(4) is bonded in a distorted single-bond geometry to one O(2) and one O(7) atom. The H(4)-O(2) bond length is 1.65 Å. The H(4)-O(7) bond length is 1.01 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one O(8) atom. The H(5)-O(8) bond length is 0.98 Å. In the sixth H site, H(6) is bonded in a distorted single-bond geometry to one O(2) and one O(8) atom. The H(6)-O(2) bond length is 1.70 Å. The H(6)-O(8) bond length is 1.00 Å. In the seventh H site, H(7) is bonded in a distorted linear geometry to one O(3) and one O(5) atom. The H(7)-O(3) bond length is 1.01 Å. The H(7)-O(5) bond length is 1.62 Å. In the eighth H site, H(8) is bonded in a single-bond geometry to one O(4) atom. The H(8)-O(4) bond length is 0.99 Å. There are eight inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one C(4), one H(3), and one H(7) atom. In the second O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Li(1), and one C(4) atom. In the third O site, O(7) is bonded in a distorted water-like geometry to one Na(1), one Na(2), one H(3), and one H(4) atom. In the fourth O site, O(8) is bonded in a 4-coordinate geometry to one Na(2), one Li(1), one H(5), and one H(6) atom. In the fifth O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Li(1), and one C(1) atom. In the sixth O site, O(2) is bonded in a 3-coordinate geometry to one C(1), one H(4), and one H(6) atom. In the seventh O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one C(2), and one H(7) atom. In the eighth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one C(3), and one H(8) atom. Linkers: 2 [O]C(=O)[C@@H](O)[C@H](O)C([O])=O ,2 [O]C(=O)[C@H](O)[C@@H](O)C([O])=O. Metal clusters: 4 [Na] ,4 [Li]. The MOF has largest included sphere 1.83 A, density 1.79 g/cm3, surface area 2961.99 m2/g, accessible volume 0.06 cm3/g