KNaReH9 crystallizes in the orthorhombic Pnma space group. K(1) is bonded in a 14-coordinate geometry to two equivalent H(1), two equivalent H(4), two equivalent H(6), four equivalent H(2), and four equivalent H(3) atoms. Na(1) is bonded in a distorted body-centered cubic geometry to two equivalent H(2), two equivalent H(3), and four equivalent H(1) atoms. Re(1) is bonded in a 9-coordinate geometry to one H(4), one H(5), one H(6), two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms. There are six inequivalent H sites. In the first H site, H(4) is bonded in a single-bond geometry to two equivalent K(1) and one Re(1) atom. In the second H site, H(5) is bonded in a single-bond geometry to one Re(1) atom. In the third H site, H(1) is bonded to one K(1), two equivalent Na(1), and one Re(1) atom to form distorted HKNa2Re tetrahedra that share corners with two equivalent H(1)KNa2Re tetrahedra, corners with eight equivalent H(3)K2NaRe tetrahedra,  an edgeedge with one H(3)K2NaRe tetrahedra, and edges with three equivalent H(1)KNa2Re tetrahedra. In the fourth H site, H(6) is bonded in a single-bond geometry to two equivalent K(1) and one Re(1) atom. In the fifth H site, H(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one Na(1), and one Re(1) atom. In the sixth H site, H(3) is bonded to two equivalent K(1), one Na(1), and one Re(1) atom to form distorted HK2NaRe tetrahedra that share corners with two equivalent H(3)K2NaRe tetrahedra, corners with eight equivalent H(1)KNa2Re tetrahedra,  an edgeedge with one H(1)KNa2Re tetrahedra, and edges with three equivalent H(3)K2NaRe tetrahedra.
KNaReH9 crystallizes in the orthorhombic Pnma space group. K(1) is bonded in a 14-coordinate geometry to two equivalent H(1), two equivalent H(4), two equivalent H(6), four equivalent H(2), and four equivalent H(3) atoms. Both K(1)-H(1) bond lengths are 2.77 Å. Both K(1)-H(4) bond lengths are 2.93 Å. Both K(1)-H(6) bond lengths are 2.93 Å. There are two shorter (2.77 Å) and two longer (2.92 Å) K(1)-H(2) bond lengths. There are two shorter (2.79 Å) and two longer (2.89 Å) K(1)-H(3) bond lengths. Na(1) is bonded in a distorted body-centered cubic geometry to two equivalent H(2), two equivalent H(3), and four equivalent H(1) atoms. Both Na(1)-H(2) bond lengths are 2.44 Å. Both Na(1)-H(3) bond lengths are 2.40 Å. There are two shorter (2.37 Å) and two longer (2.44 Å) Na(1)-H(1) bond lengths. Re(1) is bonded in a 9-coordinate geometry to one H(4), one H(5), one H(6), two equivalent H(1), two equivalent H(2), and two equivalent H(3) atoms. The Re(1)-H(4) bond length is 1.66 Å. The Re(1)-H(5) bond length is 1.68 Å. The Re(1)-H(6) bond length is 1.67 Å. Both Re(1)-H(1) bond lengths are 1.70 Å. Both Re(1)-H(2) bond lengths are 1.70 Å. Both Re(1)-H(3) bond lengths are 1.70 Å. There are six inequivalent H sites. In the first H site, H(4) is bonded in a single-bond geometry to two equivalent K(1) and one Re(1) atom. In the second H site, H(5) is bonded in a single-bond geometry to one Re(1) atom. In the third H site, H(1) is bonded to one K(1), two equivalent Na(1), and one Re(1) atom to form distorted HKNa2Re tetrahedra that share corners with two equivalent H(1)KNa2Re tetrahedra, corners with eight equivalent H(3)K2NaRe tetrahedra,  an edgeedge with one H(3)K2NaRe tetrahedra, and edges with three equivalent H(1)KNa2Re tetrahedra. In the fourth H site, H(6) is bonded in a single-bond geometry to two equivalent K(1) and one Re(1) atom. In the fifth H site, H(2) is bonded in a 4-coordinate geometry to two equivalent K(1), one Na(1), and one Re(1) atom. In the sixth H site, H(3) is bonded to two equivalent K(1), one Na(1), and one Re(1) atom to form distorted HK2NaRe tetrahedra that share corners with two equivalent H(3)K2NaRe tetrahedra, corners with eight equivalent H(1)KNa2Re tetrahedra,  an edgeedge with one H(1)KNa2Re tetrahedra, and edges with three equivalent H(3)K2NaRe tetrahedra.