The compound described by Mg3B36Si9C crystallizes in the trigonal R3m space group. Mg(1) is bonded in a 12-coordinate geometry to two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), two equivalent Si(3), and two equivalent Si(4) atoms. There are eight inequivalent B sites. In the first B site, B(7) is bonded in a 6-coordinate geometry to one B(1), two equivalent B(4), two equivalent B(5), and one Si(4) atom. In the second B site, B(1) is bonded in a 6-coordinate geometry to one B(7), two equivalent B(3), two equivalent B(5), and one Si(5) atom. In the third B site, B(8) is bonded in a 6-coordinate geometry to one B(2), two equivalent B(3), two equivalent B(6), and one Si(3) atom. In the fourth B site, B(2) is bonded in a single-bond geometry to one B(8), two equivalent B(4), two equivalent B(6), and one C(1) atom. In the fifth B site, B(3) is bonded in a 7-coordinate geometry to one Mg(1), one B(1), one B(5), one B(6), one B(8), and two equivalent B(3) atoms. In the sixth B site, B(4) is bonded in a 7-coordinate geometry to one Mg(1), one B(2), one B(5), one B(6), one B(7), and two equivalent B(4) atoms. In the seventh B site, B(5) is bonded in a 7-coordinate geometry to one Mg(1), one B(1), one B(3), one B(4), one B(6), one B(7), and one Si(3) atom. In the eighth B site, B(6) is bonded in a 7-coordinate geometry to one Mg(1), one B(2), one B(3), one B(4), one B(5), one B(8), and one Si(4) atom. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one Si(2) and three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one Si(1) and three equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one B(8), two equivalent B(5), and one Si(1) atom. In the fourth Si site, Si(4) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one B(7), two equivalent B(6), and one Si(2) atom. In the fifth Si site, Si(5) is bonded in a distorted tetrahedral geometry to three equivalent B(1) and one C(1) atom. C(1) is bonded in a tetrahedral geometry to three equivalent B(2) and one Si(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si9B36C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.002
_cell_length_b   8.002
_cell_length_c   8.002
_cell_angle_alpha   78.308
_cell_angle_beta   78.308
_cell_angle_gamma   78.308
_symmetry_Int_Tables_number   1
_cell_volume   484.342
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Mg  Mg0  1  0.499  1.000  0.499  1.0
  Mg  Mg1  1  1.000  0.499  0.499  1.0
  Mg  Mg2  1  0.499  0.499  1.000  1.0
  Si  Si3  1  0.573  0.573  0.573  1.0
  Si  Si4  1  0.429  0.429  0.429  1.0
  Si  Si5  1  0.739  0.739  0.343  1.0
  Si  Si6  1  0.739  0.343  0.739  1.0
  Si  Si7  1  0.343  0.739  0.739  1.0
  Si  Si8  1  0.262  0.262  0.655  1.0
  Si  Si9  1  0.262  0.655  0.262  1.0
  Si  Si10  1  0.655  0.262  0.262  1.0
  Si  Si11  1  0.956  0.956  0.956  1.0
  B  B12  1  0.704  0.994  0.994  1.0
  B  B13  1  0.994  0.994  0.704  1.0
  B  B14  1  0.994  0.704  0.994  1.0
  B  B15  1  0.276  0.018  0.018  1.0
  B  B16  1  0.018  0.018  0.276  1.0
  B  B17  1  0.018  0.276  0.018  1.0
  B  B18  1  0.625  0.981  0.800  1.0
  B  B19  1  0.981  0.800  0.625  1.0
  B  B20  1  0.800  0.625  0.981  1.0
  B  B21  1  0.981  0.625  0.800  1.0
  B  B22  1  0.625  0.800  0.981  1.0
  B  B23  1  0.800  0.981  0.625  1.0
  B  B24  1  0.373  0.023  0.203  1.0
  B  B25  1  0.023  0.203  0.373  1.0
  B  B26  1  0.203  0.373  0.023  1.0
  B  B27  1  0.023  0.373  0.203  1.0
  B  B28  1  0.373  0.203  0.023  1.0
  B  B29  1  0.203  0.023  0.373  1.0
  B  B30  1  0.581  0.179  0.892  1.0
  B  B31  1  0.179  0.892  0.581  1.0
  B  B32  1  0.892  0.581  0.179  1.0
  B  B33  1  0.179  0.581  0.892  1.0
  B  B34  1  0.581  0.892  0.179  1.0
  B  B35  1  0.892  0.179  0.581  1.0
  B  B36  1  0.411  0.826  0.109  1.0
  B  B37  1  0.826  0.109  0.411  1.0
  B  B38  1  0.109  0.411  0.826  1.0
  B  B39  1  0.826  0.411  0.109  1.0
  B  B40  1  0.411  0.109  0.826  1.0
  B  B41  1  0.109  0.826  0.411  1.0
  B  B42  1  0.556  0.126  0.126  1.0
  B  B43  1  0.126  0.126  0.556  1.0
  B  B44  1  0.126  0.556  0.126  1.0
  B  B45  1  0.435  0.878  0.878  1.0
  B  B46  1  0.878  0.878  0.435  1.0
  B  B47  1  0.878  0.435  0.878  1.0
  C  C48  1  0.068  0.068  0.068  1.0
[/CIF]
.
The compound described by Mg3B36Si9C crystallizes in the trigonal R3m space group. Mg(1) is bonded in a 12-coordinate geometry to two equivalent B(3), two equivalent B(4), two equivalent B(5), two equivalent B(6), two equivalent Si(3), and two equivalent Si(4) atoms. There are eight inequivalent B sites. In the first B site, B(7) is bonded in a 6-coordinate geometry to one B(1), two equivalent B(4), two equivalent B(5), and one Si(4) atom. In the second B site, B(1) is bonded in a 6-coordinate geometry to one B(7), two equivalent B(3), two equivalent B(5), and one Si(5) atom. In the third B site, B(8) is bonded in a 6-coordinate geometry to one B(2), two equivalent B(3), two equivalent B(6), and one Si(3) atom. In the fourth B site, B(2) is bonded in a single-bond geometry to one B(8), two equivalent B(4), two equivalent B(6), and one C(1) atom. In the fifth B site, B(3) is bonded in a 7-coordinate geometry to one Mg(1), one B(1), one B(5), one B(6), one B(8), and two equivalent B(3) atoms. In the sixth B site, B(4) is bonded in a 7-coordinate geometry to one Mg(1), one B(2), one B(5), one B(6), one B(7), and two equivalent B(4) atoms. In the seventh B site, B(5) is bonded in a 7-coordinate geometry to one Mg(1), one B(1), one B(3), one B(4), one B(6), one B(7), and one Si(3) atom. In the eighth B site, B(6) is bonded in a 7-coordinate geometry to one Mg(1), one B(2), one B(3), one B(4), one B(5), one B(8), and one Si(4) atom. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one Si(2) and three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one Si(1) and three equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one B(8), two equivalent B(5), and one Si(1) atom. In the fourth Si site, Si(4) is bonded in a 6-coordinate geometry to two equivalent Mg(1), one B(7), two equivalent B(6), and one Si(2) atom. In the fifth Si site, Si(5) is bonded in a distorted tetrahedral geometry to three equivalent B(1) and one C(1) atom. C(1) is bonded in a tetrahedral geometry to three equivalent B(2) and one Si(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Si9B36C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.002
_cell_length_b   8.002
_cell_length_c   8.002
_cell_angle_alpha   78.308
_cell_angle_beta   78.308
_cell_angle_gamma   78.308
_symmetry_Int_Tables_number   1
_cell_volume   484.342
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Mg  Mg0  1  0.499  1.000  0.499  1.0
  Mg  Mg1  1  1.000  0.499  0.499  1.0
  Mg  Mg2  1  0.499  0.499  1.000  1.0
  Si  Si3  1  0.573  0.573  0.573  1.0
  Si  Si4  1  0.429  0.429  0.429  1.0
  Si  Si5  1  0.739  0.739  0.343  1.0
  Si  Si6  1  0.739  0.343  0.739  1.0
  Si  Si7  1  0.343  0.739  0.739  1.0
  Si  Si8  1  0.262  0.262  0.655  1.0
  Si  Si9  1  0.262  0.655  0.262  1.0
  Si  Si10  1  0.655  0.262  0.262  1.0
  Si  Si11  1  0.956  0.956  0.956  1.0
  B  B12  1  0.704  0.994  0.994  1.0
  B  B13  1  0.994  0.994  0.704  1.0
  B  B14  1  0.994  0.704  0.994  1.0
  B  B15  1  0.276  0.018  0.018  1.0
  B  B16  1  0.018  0.018  0.276  1.0
  B  B17  1  0.018  0.276  0.018  1.0
  B  B18  1  0.625  0.981  0.800  1.0
  B  B19  1  0.981  0.800  0.625  1.0
  B  B20  1  0.800  0.625  0.981  1.0
  B  B21  1  0.981  0.625  0.800  1.0
  B  B22  1  0.625  0.800  0.981  1.0
  B  B23  1  0.800  0.981  0.625  1.0
  B  B24  1  0.373  0.023  0.203  1.0
  B  B25  1  0.023  0.203  0.373  1.0
  B  B26  1  0.203  0.373  0.023  1.0
  B  B27  1  0.023  0.373  0.203  1.0
  B  B28  1  0.373  0.203  0.023  1.0
  B  B29  1  0.203  0.023  0.373  1.0
  B  B30  1  0.581  0.179  0.892  1.0
  B  B31  1  0.179  0.892  0.581  1.0
  B  B32  1  0.892  0.581  0.179  1.0
  B  B33  1  0.179  0.581  0.892  1.0
  B  B34  1  0.581  0.892  0.179  1.0
  B  B35  1  0.892  0.179  0.581  1.0
  B  B36  1  0.411  0.826  0.109  1.0
  B  B37  1  0.826  0.109  0.411  1.0
  B  B38  1  0.109  0.411  0.826  1.0
  B  B39  1  0.826  0.411  0.109  1.0
  B  B40  1  0.411  0.109  0.826  1.0
  B  B41  1  0.109  0.826  0.411  1.0
  B  B42  1  0.556  0.126  0.126  1.0
  B  B43  1  0.126  0.126  0.556  1.0
  B  B44  1  0.126  0.556  0.126  1.0
  B  B45  1  0.435  0.878  0.878  1.0
  B  B46  1  0.878  0.878  0.435  1.0
  B  B47  1  0.878  0.435  0.878  1.0
  C  C48  1  0.068  0.068  0.068  1.0
[/CIF]
.