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USi crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. U4+ is bonded in a 7-coordinate geometry to seven equivalent Si4- atoms. There are a spread of U–Si bond distances ranging from 2.90–3.11 Å. Si4- is bonded in a 9-coordinate geometry to seven equivalent U4+ and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.43 Å.
U3Si2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 6-coordinate geometry to six equivalent Si atoms. There are two shorter (2.83 Å) and four longer (2.96 Å) U–Si bond lengths. In the second U site, U is bonded in a square co-planar geometry to four equivalent Si atoms. All U–Si bond lengths are 2.91 Å. Si is bonded in a 9-coordinate geometry to eight U and one Si atom. The Si–Si bond length is 2.36 Å.
USi3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. U4+ is bonded to twelve equivalent Si+1.33- atoms to form a mixture of face and corner-sharing USi12 cuboctahedra. All U–Si bond lengths are 2.85 Å. Si+1.33- is bonded in a distorted square co-planar geometry to four equivalent U4+ atoms.
U3Si is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. U is bonded to eight equivalent U and four equivalent Si atoms to form distorted UU8Si4 cuboctahedra that share corners with twelve equivalent UU8Si4 cuboctahedra, edges with eight equivalent SiU12 cuboctahedra, edges with sixteen equivalent UU8Si4 cuboctahedra, faces with four equivalent SiU12 cuboctahedra, and faces with fourteen equivalent UU8Si4 cuboctahedra. All U–U bond lengths are 3.01 Å. All U–Si bond lengths are 3.01 Å. Si is bonded to twelve equivalent U atoms to form SiU12 cuboctahedra that share corners with twelve equivalent SiU12 cuboctahedra, edges with twenty-four equivalent UU8Si4 cuboctahedra, faces with six equivalent SiU12 cuboctahedra, and faces with twelve equivalent UU8Si4 cuboctahedra.
U3Si is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded to eight equivalent U and four equivalent Si atoms to form distorted UU8Si4 cuboctahedra that share corners with twelve equivalent UU8Si4 cuboctahedra, edges with eight equivalent SiU12 cuboctahedra, faces with four equivalent SiU12 cuboctahedra, and faces with six equivalent UU8Si4 cuboctahedra. There are four shorter (2.86 Å) and four longer (3.15 Å) U–U bond lengths. All U–Si bond lengths are 3.01 Å. In the second U site, U is bonded in a 12-coordinate geometry to eight U and four equivalent Si atoms. All U–U bond lengths are 3.02 Å. All U–Si bond lengths are 3.01 Å. Si is bonded to twelve U atoms to form SiU12 cuboctahedra that share corners with twelve equivalent SiU12 cuboctahedra, edges with eight equivalent UU8Si4 cuboctahedra, faces with four equivalent UU8Si4 cuboctahedra, and faces with six equivalent SiU12 cuboctahedra.
USi2 is hexagonal omega structure-like structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. U is bonded to twelve equivalent Si atoms to form a mixture of edge and face-sharing USi12 cuboctahedra. There are eight shorter (2.99 Å) and four longer (3.07 Å) U–Si bond lengths. Si is bonded in a 9-coordinate geometry to six equivalent U and three equivalent Si atoms. There are two shorter (2.30 Å) and one longer (2.31 Å) Si–Si bond lengths.
USi2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. U is bonded to twelve equivalent Si atoms to form a mixture of edge and face-sharing USi12 cuboctahedra. All U–Si bond lengths are 3.02 Å. Si is bonded in a 9-coordinate geometry to six equivalent U and three equivalent Si atoms. All Si–Si bond lengths are 2.32 Å.
U3Si is beta Cu3Ti-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent U sites. In the first U site, U is bonded in a 4-coordinate geometry to eight U and four Si atoms. There are a spread of U–U bond distances ranging from 2.90–3.14 Å. All U–Si bond lengths are 3.01 Å. In the second U site, U is bonded in a 4-coordinate geometry to eight U and four Si atoms. There are a spread of U–U bond distances ranging from 2.90–3.14 Å. All U–Si bond lengths are 3.01 Å. In the third U site, U is bonded in a 12-coordinate geometry to eight U and four Si atoms. There are two shorter (2.81 Å) and two longer (3.19 Å) U–U bond lengths. All U–Si bond lengths are 3.01 Å. In the fourth U site, U is bonded in a 12-coordinate geometry to eight U and four Si atoms. There are a spread of U–U bond distances ranging from 2.81–3.18 Å. All U–Si bond lengths are 3.01 Å. In the fifth U site, U is bonded in a 12-coordinate geometry to eight U and four Si atoms. There are three shorter (3.01 Å) and one longer (3.02 Å) U–Si bond lengths. In the sixth U site, U is bonded in a 12-coordinate geometry to eight U and four Si atoms. There are two shorter (3.01 Å) and two longer (3.02 Å) U–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded to twelve U atoms to form a mixture of corner and face-sharing SiU12 cuboctahedra. In the second Si site, Si is bonded to twelve U atoms to form a mixture of corner and face-sharing SiU12 cuboctahedra.