MnCu2SiS4 is Stannite-like structured and crystallizes in the orthorhombic Pmn2_1 space group. Mn(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form MnS4 tetrahedra that share corners with four equivalent Si(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. Cu(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Mn(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Si(1)S4 tetrahedra. Si(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form SiS4 tetrahedra that share corners with four equivalent Mn(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra. In the second S site, S(2) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra. In the third S site, S(3) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra.
MnCu2SiS4 is Stannite-like structured and crystallizes in the orthorhombic Pmn2_1 space group. Mn(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form MnS4 tetrahedra that share corners with four equivalent Si(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. The Mn(1)-S(1) bond length is 2.39 Å. The Mn(1)-S(3) bond length is 2.41 Å. Both Mn(1)-S(2) bond lengths are 2.43 Å. Cu(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with four equivalent Mn(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Si(1)S4 tetrahedra. The Cu(1)-S(1) bond length is 2.30 Å. The Cu(1)-S(3) bond length is 2.31 Å. There is one shorter (2.30 Å) and one longer (2.33 Å) Cu(1)-S(2) bond length. Si(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form SiS4 tetrahedra that share corners with four equivalent Mn(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. The Si(1)-S(1) bond length is 2.16 Å. The Si(1)-S(3) bond length is 2.15 Å. Both Si(1)-S(2) bond lengths are 2.16 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra. In the second S site, S(2) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra. In the third S site, S(3) is bonded to one Mn(1), two equivalent Cu(1), and one Si(1) atom to form corner-sharing SMnCu2Si tetrahedra.