RbLaSiS4 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one S(3), three equivalent S(2), and four equivalent S(1) atoms. La(1) is bonded in a 8-coordinate geometry to one S(2), three equivalent S(3), and four equivalent S(1) atoms. Si(1) is bonded in a tetrahedral geometry to one S(2), one S(3), and two equivalent S(1) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Rb(1), two equivalent La(1), and one Si(1) atom. In the second S site, S(2) is bonded to three equivalent Rb(1), one La(1), and one Si(1) atom to form distorted corner-sharing SRb3LaSi trigonal bipyramids. In the third S site, S(3) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent La(1), and one Si(1) atom.
RbLaSiS4 crystallizes in the orthorhombic Pnma space group. Rb(1) is bonded in a 8-coordinate geometry to one S(3), three equivalent S(2), and four equivalent S(1) atoms. The Rb(1)-S(3) bond length is 3.46 Å. There are two shorter (3.52 Å) and one longer (3.56 Å) Rb(1)-S(2) bond length. There are two shorter (3.56 Å) and two longer (3.63 Å) Rb(1)-S(1) bond lengths. La(1) is bonded in a 8-coordinate geometry to one S(2), three equivalent S(3), and four equivalent S(1) atoms. The La(1)-S(2) bond length is 2.91 Å. There is one shorter (2.92 Å) and two longer (3.51 Å) La(1)-S(3) bond lengths. There are two shorter (2.97 Å) and two longer (2.99 Å) La(1)-S(1) bond lengths. Si(1) is bonded in a tetrahedral geometry to one S(2), one S(3), and two equivalent S(1) atoms. The Si(1)-S(2) bond length is 2.11 Å. The Si(1)-S(3) bond length is 2.14 Å. Both Si(1)-S(1) bond lengths are 2.14 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to two equivalent Rb(1), two equivalent La(1), and one Si(1) atom. In the second S site, S(2) is bonded to three equivalent Rb(1), one La(1), and one Si(1) atom to form distorted corner-sharing SRb3LaSi trigonal bipyramids. In the third S site, S(3) is bonded in a 5-coordinate geometry to one Rb(1), three equivalent La(1), and one Si(1) atom.