CMn4MoSi crystallizes in the orthorhombic Cmc2_1 space group. Mo(1) is bonded in a 1-coordinate geometry to one Mn(3), three equivalent Si(1), and one C(1) atom. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 2-coordinate geometry to two equivalent Si(1), one C(1), and one C(2) atom. In the second Mn site, Mn(2) is bonded in a distorted water-like geometry to two equivalent Si(1), one C(1), and one C(2) atom. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Mo(1), two equivalent Si(1), one C(1), and one C(2) atom. In the fourth Mn site, Mn(4) is bonded in a 2-coordinate geometry to two equivalent Si(1), one C(1), and one C(2) atom. In the fifth Mn site, Mn(5) is bonded in a distorted single-bond geometry to three equivalent Si(1) and one C(2) atom. Si(1) is bonded to three equivalent Mo(1), one Mn(3), one Mn(4), two equivalent Mn(1), two equivalent Mn(2), and three equivalent Mn(5) atoms to form a mixture of distorted face, corner, and edge-sharing SiMn9Mo3 cuboctahedra. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to two equivalent Mo(1), one Mn(3), one Mn(4), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the second C site, C(2) is bonded in a 8-coordinate geometry to one Mn(3), one Mn(4), two equivalent Mn(1), two equivalent Mn(2), and two equivalent Mn(5) atoms.
CMn4MoSi crystallizes in the orthorhombic Cmc2_1 space group. Mo(1) is bonded in a 1-coordinate geometry to one Mn(3), three equivalent Si(1), and one C(1) atom. The Mo(1)-Mn(3) bond length is 2.66 Å. There are a spread of Mo(1)-Si(1) bond distances ranging from 2.65-2.73 Å. The Mo(1)-C(1) bond length is 2.13 Å. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 2-coordinate geometry to two equivalent Si(1), one C(1), and one C(2) atom. There is one shorter (2.33 Å) and one longer (2.47 Å) Mn(1)-Si(1) bond length. The Mn(1)-C(1) bond length is 2.02 Å. The Mn(1)-C(2) bond length is 2.04 Å. In the second Mn site, Mn(2) is bonded in a distorted water-like geometry to two equivalent Si(1), one C(1), and one C(2) atom. There is one shorter (2.39 Å) and one longer (2.42 Å) Mn(2)-Si(1) bond length. The Mn(2)-C(1) bond length is 1.99 Å. The Mn(2)-C(2) bond length is 2.04 Å. In the third Mn site, Mn(3) is bonded in a 6-coordinate geometry to two equivalent Mo(1), two equivalent Si(1), one C(1), and one C(2) atom. Both Mn(3)-Si(1) bond lengths are 2.54 Å. The Mn(3)-C(1) bond length is 2.71 Å. The Mn(3)-C(2) bond length is 2.56 Å. In the fourth Mn site, Mn(4) is bonded in a 2-coordinate geometry to two equivalent Si(1), one C(1), and one C(2) atom. Both Mn(4)-Si(1) bond lengths are 2.59 Å. The Mn(4)-C(1) bond length is 2.33 Å. The Mn(4)-C(2) bond length is 2.25 Å. In the fifth Mn site, Mn(5) is bonded in a distorted single-bond geometry to three equivalent Si(1) and one C(2) atom. There are a spread of Mn(5)-Si(1) bond distances ranging from 2.63-2.71 Å. The Mn(5)-C(2) bond length is 2.05 Å. Si(1) is bonded to three equivalent Mo(1), one Mn(3), one Mn(4), two equivalent Mn(1), two equivalent Mn(2), and three equivalent Mn(5) atoms to form a mixture of distorted face, corner, and edge-sharing SiMn9Mo3 cuboctahedra. There are two inequivalent C sites. In the first C site, C(1) is bonded in a 7-coordinate geometry to two equivalent Mo(1), one Mn(3), one Mn(4), two equivalent Mn(1), and two equivalent Mn(2) atoms. In the second C site, C(2) is bonded in a 8-coordinate geometry to one Mn(3), one Mn(4), two equivalent Mn(1), two equivalent Mn(2), and two equivalent Mn(5) atoms.