Mn3IrSi crystallizes in the cubic P2_13 space group. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. In the second Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. In the third Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. In the fourth Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. In the fifth Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. Ir(1) is bonded to nine Mn(1,1,1) and three equivalent Si(1) atoms to form IrMn9Si3 cuboctahedra that share corners with six equivalent Ir(1)Mn9Si3 cuboctahedra, corners with nine equivalent Si(1)Mn9Ir3 cuboctahedra, faces with four equivalent Si(1)Mn9Ir3 cuboctahedra, and faces with six equivalent Ir(1)Mn9Si3 cuboctahedra. Si(1) is bonded to nine Mn(1,1,1,1,1) and three equivalent Ir(1) atoms to form distorted SiMn9Ir3 cuboctahedra that share corners with six equivalent Si(1)Mn9Ir3 cuboctahedra, corners with nine equivalent Ir(1)Mn9Si3 cuboctahedra, faces with four equivalent Ir(1)Mn9Si3 cuboctahedra, and faces with six equivalent Si(1)Mn9Ir3 cuboctahedra.
Mn3IrSi crystallizes in the cubic P2_13 space group. There are five inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. There are a spread of Mn(1)-Mn(1,1,1,1) bond distances ranging from 2.62-2.78 Å. There are a spread of Mn(1)-Ir(1) bond distances ranging from 2.60-2.72 Å. There is one shorter (2.53 Å) and two longer (2.72 Å) Mn(1)-Si(1) bond lengths. In the second Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. There are a spread of Mn(1)-Mn(1,1) bond distances ranging from 2.62-2.78 Å. There are a spread of Mn(1)-Ir(1) bond distances ranging from 2.60-2.72 Å. There is one shorter (2.53 Å) and two longer (2.72 Å) Mn(1)-Si(1) bond lengths. In the third Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. There are a spread of Mn(1)-Mn(1,1) bond distances ranging from 2.62-2.78 Å. There are a spread of Mn(1)-Ir(1) bond distances ranging from 2.60-2.72 Å. There is one shorter (2.53 Å) and two longer (2.72 Å) Mn(1)-Si(1) bond lengths. In the fourth Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. Both Mn(1)-Mn(1) bond lengths are 2.78 Å. There are a spread of Mn(1)-Ir(1) bond distances ranging from 2.60-2.72 Å. There is one shorter (2.53 Å) and two longer (2.72 Å) Mn(1)-Si(1) bond lengths. In the fifth Mn site, Mn(1) is bonded in a 12-coordinate geometry to six Mn(1,1,1,1); three equivalent Ir(1); and three equivalent Si(1) atoms. There are a spread of Mn(1)-Mn(1,1) bond distances ranging from 2.62-2.78 Å. There are a spread of Mn(1)-Ir(1) bond distances ranging from 2.60-2.72 Å. There is one shorter (2.53 Å) and two longer (2.72 Å) Mn(1)-Si(1) bond lengths. Ir(1) is bonded to nine Mn(1,1,1) and three equivalent Si(1) atoms to form IrMn9Si3 cuboctahedra that share corners with six equivalent Ir(1)Mn9Si3 cuboctahedra, corners with nine equivalent Si(1)Mn9Ir3 cuboctahedra, faces with four equivalent Si(1)Mn9Ir3 cuboctahedra, and faces with six equivalent Ir(1)Mn9Si3 cuboctahedra. All Ir(1)-Si(1) bond lengths are 2.39 Å. Si(1) is bonded to nine Mn(1,1,1,1,1) and three equivalent Ir(1) atoms to form distorted SiMn9Ir3 cuboctahedra that share corners with six equivalent Si(1)Mn9Ir3 cuboctahedra, corners with nine equivalent Ir(1)Mn9Si3 cuboctahedra, faces with four equivalent Ir(1)Mn9Si3 cuboctahedra, and faces with six equivalent Si(1)Mn9Ir3 cuboctahedra.