K2ZnH4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one H(2), two equivalent H(1), and two equivalent H(3) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one H(2), two equivalent H(3), and four equivalent H(1) atoms. Zn(1) is bonded in a tetrahedral geometry to one H(2), one H(3), and two equivalent H(1) atoms. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one K(1), two equivalent K(2), and one Zn(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one Zn(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent K(1), two equivalent K(2), and one Zn(1) atom.
K2ZnH4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one H(2), two equivalent H(1), and two equivalent H(3) atoms. The K(1)-H(2) bond length is 2.82 Å. Both K(1)-H(1) bond lengths are 2.95 Å. Both K(1)-H(3) bond lengths are 2.91 Å. In the second K site, K(2) is bonded in a 7-coordinate geometry to one H(2), two equivalent H(3), and four equivalent H(1) atoms. The K(2)-H(2) bond length is 2.82 Å. There is one shorter (2.75 Å) and one longer (2.82 Å) K(2)-H(3) bond length. There are two shorter (2.72 Å) and two longer (2.80 Å) K(2)-H(1) bond lengths. Zn(1) is bonded in a tetrahedral geometry to one H(2), one H(3), and two equivalent H(1) atoms. The Zn(1)-H(2) bond length is 1.64 Å. The Zn(1)-H(3) bond length is 1.65 Å. Both Zn(1)-H(1) bond lengths are 1.64 Å. There are three inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one K(1), two equivalent K(2), and one Zn(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one Zn(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent K(1), two equivalent K(2), and one Zn(1) atom.