RbMg6Si crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Si(1) atoms. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 1-coordinate geometry to two equivalent Rb(1), two equivalent Mg(4), and one Si(1) atom. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent Mg(4) and four equivalent Mg(3) atoms. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to one Rb(1), two equivalent Mg(2), and two equivalent Si(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Mg(2), and four equivalent Mg(1) atoms. Si(1) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Mg(1), and four equivalent Mg(3) atoms.
RbMg6Si crystallizes in the orthorhombic Amm2 space group. Rb(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Si(1) atoms. Both Rb(1)-Mg(3) bond lengths are 3.49 Å. Both Rb(1)-Mg(4) bond lengths are 3.48 Å. All Rb(1)-Mg(1) bond lengths are 3.61 Å. Both Rb(1)-Si(1) bond lengths are 3.57 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 1-coordinate geometry to two equivalent Rb(1), two equivalent Mg(4), and one Si(1) atom. Both Mg(1)-Mg(4) bond lengths are 3.23 Å. The Mg(1)-Si(1) bond length is 2.76 Å. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to two equivalent Mg(4) and four equivalent Mg(3) atoms. Both Mg(2)-Mg(4) bond lengths are 3.14 Å. All Mg(2)-Mg(3) bond lengths are 3.14 Å. In the third Mg site, Mg(3) is bonded in a distorted water-like geometry to one Rb(1), two equivalent Mg(2), and two equivalent Si(1) atoms. Both Mg(3)-Si(1) bond lengths are 2.84 Å. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Mg(2), and four equivalent Mg(1) atoms. Si(1) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Mg(1), and four equivalent Mg(3) atoms.