MgNb2PdS6 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(2), one S(6), and two equivalent S(5) atoms to form MgS4 tetrahedra that share corners with four equivalent Nb(1)S7 pentagonal bipyramids, corners with two equivalent Mg(1)S4 tetrahedra, and  an edgeedge with one Nb(1)S7 pentagonal bipyramid. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one S(3), two equivalent S(2), two equivalent S(4), and two equivalent S(5) atoms to form distorted NbS7 pentagonal bipyramids that share corners with four equivalent Mg(1)S4 tetrahedra,  an edgeedge with one Mg(1)S4 tetrahedra, and faces with two equivalent Nb(1)S7 pentagonal bipyramids. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one S(4), two equivalent S(1), two equivalent S(3), and two equivalent S(6) atoms. Pd(1) is bonded in a square co-planar geometry to one S(1), one S(2), one S(5), and one S(6) atom. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted T-shaped geometry to two equivalent Nb(2) and one Pd(1) atom. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Nb(1), and one Pd(1) atom. In the third S site, S(3) is bonded in a trigonal non-coplanar geometry to one Nb(1) and two equivalent Nb(2) atoms. In the fourth S site, S(4) is bonded in a distorted trigonal non-coplanar geometry to one Nb(2) and two equivalent Nb(1) atoms. In the fifth S site, S(5) is bonded to two equivalent Mg(1), two equivalent Nb(1), and one Pd(1) atom to form distorted SMg2Nb2Pd trigonal bipyramids that share corners with three equivalent S(6)MgNb2Pd trigonal pyramids and edges with two equivalent S(5)Mg2Nb2Pd trigonal bipyramids. In the sixth S site, S(6) is bonded to one Mg(1), two equivalent Nb(2), and one Pd(1) atom to form distorted SMgNb2Pd trigonal pyramids that share corners with three equivalent S(5)Mg2Nb2Pd trigonal bipyramids and corners with two equivalent S(6)MgNb2Pd trigonal pyramids.
MgNb2PdS6 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(2), one S(6), and two equivalent S(5) atoms to form MgS4 tetrahedra that share corners with four equivalent Nb(1)S7 pentagonal bipyramids, corners with two equivalent Mg(1)S4 tetrahedra, and  an edgeedge with one Nb(1)S7 pentagonal bipyramid. The Mg(1)-S(2) bond length is 2.42 Å. The Mg(1)-S(6) bond length is 2.46 Å. Both Mg(1)-S(5) bond lengths are 2.46 Å. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one S(3), two equivalent S(2), two equivalent S(4), and two equivalent S(5) atoms to form distorted NbS7 pentagonal bipyramids that share corners with four equivalent Mg(1)S4 tetrahedra,  an edgeedge with one Mg(1)S4 tetrahedra, and faces with two equivalent Nb(1)S7 pentagonal bipyramids. The Nb(1)-S(3) bond length is 2.58 Å. Both Nb(1)-S(2) bond lengths are 2.52 Å. Both Nb(1)-S(4) bond lengths are 2.53 Å. Both Nb(1)-S(5) bond lengths are 2.60 Å. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one S(4), two equivalent S(1), two equivalent S(3), and two equivalent S(6) atoms. The Nb(2)-S(4) bond length is 2.65 Å. Both Nb(2)-S(1) bond lengths are 2.50 Å. Both Nb(2)-S(3) bond lengths are 2.54 Å. Both Nb(2)-S(6) bond lengths are 2.53 Å. Pd(1) is bonded in a square co-planar geometry to one S(1), one S(2), one S(5), and one S(6) atom. The Pd(1)-S(1) bond length is 2.36 Å. The Pd(1)-S(2) bond length is 2.42 Å. The Pd(1)-S(5) bond length is 2.43 Å. The Pd(1)-S(6) bond length is 2.45 Å. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted T-shaped geometry to two equivalent Nb(2) and one Pd(1) atom. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Nb(1), and one Pd(1) atom. In the third S site, S(3) is bonded in a trigonal non-coplanar geometry to one Nb(1) and two equivalent Nb(2) atoms. In the fourth S site, S(4) is bonded in a distorted trigonal non-coplanar geometry to one Nb(2) and two equivalent Nb(1) atoms. In the fifth S site, S(5) is bonded to two equivalent Mg(1), two equivalent Nb(1), and one Pd(1) atom to form distorted SMg2Nb2Pd trigonal bipyramids that share corners with three equivalent S(6)MgNb2Pd trigonal pyramids and edges with two equivalent S(5)Mg2Nb2Pd trigonal bipyramids. In the sixth S site, S(6) is bonded to one Mg(1), two equivalent Nb(2), and one Pd(1) atom to form distorted SMgNb2Pd trigonal pyramids that share corners with three equivalent S(5)Mg2Nb2Pd trigonal bipyramids and corners with two equivalent S(6)MgNb2Pd trigonal pyramids.