Si is Theoretical Carbon Structure-like structured and crystallizes in the cubic I-43m space group. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Si(4) and three equivalent Si(1) atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. In the second Si site, Si(2) is bonded to one Si(3) and three equivalent Si(4) atoms to form corner-sharing SiSi4 tetrahedra. In the third Si site, Si(3) is bonded to four equivalent Si(2) atoms to form corner-sharing SiSi4 tetrahedra. In the fourth Si site, Si(4) is bonded to one Si(2), one Si(4), and two equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra.
Si is Theoretical Carbon Structure-like structured and crystallizes in the cubic I-43m space group. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one Si(4) and three equivalent Si(1) atoms to form a mixture of edge and corner-sharing SiSi4 tetrahedra. The Si(1)-Si(4) bond length is 2.37 Å. There is one shorter (2.33 Å) and two longer (2.36 Å) Si(1)-Si(1) bond lengths. In the second Si site, Si(2) is bonded to one Si(3) and three equivalent Si(4) atoms to form corner-sharing SiSi4 tetrahedra. The Si(2)-Si(3) bond length is 2.34 Å. All Si(2)-Si(4) bond lengths are 2.38 Å. In the third Si site, Si(3) is bonded to four equivalent Si(2) atoms to form corner-sharing SiSi4 tetrahedra. In the fourth Si site, Si(4) is bonded to one Si(2), one Si(4), and two equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra. The Si(4)-Si(4) bond length is 2.39 Å.