The material structure described by Cr6CuSi2(Pb5O17)2 crystallizes in the triclinic P-1 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(5), one O(6), one O(7), and one O(8) atom. In the third Cr site, Cr(3) is bonded to one O(10), one O(11), one O(12), and one O(9) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. Cu(1) is bonded to two equivalent O(11), two equivalent O(14), and two equivalent O(17) atoms to form distorted CuO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra and corners with two equivalent Si(1)O4 tetrahedra. There are five inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 7-coordinate geometry to one O(12), one O(13), one O(15), one O(2), one O(4), one O(5), and one O(7) atom. In the second Pb site, Pb(2) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(17), one O(2), one O(3), and one O(5) atom. In the third Pb site, Pb(3) is bonded in a distorted pentagonal planar geometry to one O(11), one O(15), one O(17), one O(3), and one O(7) atom. In the fourth Pb site, Pb(4) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(11), one O(16), and one O(8) atom. In the fifth Pb site, Pb(5) is bonded in a 5-coordinate geometry to one O(10), one O(13), one O(15), one O(16), and one O(5) atom. Si(1) is bonded to one O(13), one O(14), one O(15), and one O(16) atom to form SiO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are seventeen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cr(1) and one Pb(4) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(1), one Pb(1), and one Pb(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1), one Pb(2), and one Pb(3) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Cr(1) and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Cr(2), one Pb(1), one Pb(2), and one Pb(5) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2), one Pb(1), and one Pb(3) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(4) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one Cr(3) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one Cr(3), one Pb(4), and one Pb(5) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Cr(3), one Cu(1), one Pb(3), and one Pb(4) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Cr(3), one Pb(1), and one Pb(2) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Pb(1), one Pb(5), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Cu(1), one Pb(2), and one Si(1) atom. In the fifteenth O site, O(15) is bonded in a distorted single-bond geometry to one Pb(1), one Pb(3), one Pb(5), and one Si(1) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one Pb(4), one Pb(5), and one Si(1) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Pb(2), and one Pb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr6CuSi2(Pb5O17)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.797
_cell_length_b   10.110
_cell_length_c   10.117
_cell_angle_alpha   65.070
_cell_angle_beta   71.670
_cell_angle_gamma   68.369
_symmetry_Int_Tables_number   1
_cell_volume   829.495
_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
  Cr  Cr0  1  0.034  0.645  0.279  1.0
  Cr  Cr1  1  0.966  0.355  0.721  1.0
  Cr  Cr2  1  0.735  0.846  0.982  1.0
  Cr  Cr3  1  0.265  0.154  0.018  1.0
  Cr  Cr4  1  0.777  0.165  0.512  1.0
  Cr  Cr5  1  0.223  0.835  0.488  1.0
  Cu  Cu6  1  0.500  0.000  0.500  1.0
  Si  Si7  1  0.479  0.334  0.208  1.0
  Si  Si8  1  0.521  0.666  0.792  1.0
  Pb  Pb9  1  0.365  0.739  0.156  1.0
  Pb  Pb10  1  0.635  0.261  0.844  1.0
  Pb  Pb11  1  0.355  0.332  0.574  1.0
  Pb  Pb12  1  0.645  0.668  0.426  1.0
  Pb  Pb13  1  0.182  0.972  0.785  1.0
  Pb  Pb14  1  0.818  0.028  0.215  1.0
  Pb  Pb15  1  0.144  0.253  0.327  1.0
  Pb  Pb16  1  0.856  0.747  0.673  1.0
  Pb  Pb17  1  0.763  0.468  0.083  1.0
  Pb  Pb18  1  0.237  0.532  0.917  1.0
  O  O19  1  0.983  0.518  0.254  1.0
  O  O20  1  0.017  0.482  0.746  1.0
  O  O21  1  0.181  0.561  0.362  1.0
  O  O22  1  0.819  0.439  0.638  1.0
  O  O23  1  0.115  0.264  0.619  1.0
  O  O24  1  0.885  0.736  0.381  1.0
  O  O25  1  0.083  0.772  0.118  1.0
  O  O26  1  0.917  0.228  0.882  1.0
  O  O27  1  0.644  0.729  0.133  1.0
  O  O28  1  0.356  0.271  0.867  1.0
  O  O29  1  0.631  0.945  0.856  1.0
  O  O30  1  0.369  0.055  0.144  1.0
  O  O31  1  0.779  0.965  0.026  1.0
  O  O32  1  0.221  0.035  0.974  1.0
  O  O33  1  0.889  0.732  0.911  1.0
  O  O34  1  0.111  0.268  0.089  1.0
  O  O35  1  0.893  0.087  0.627  1.0
  O  O36  1  0.107  0.913  0.373  1.0
  O  O37  1  0.858  0.260  0.345  1.0
  O  O38  1  0.142  0.740  0.655  1.0
  O  O39  1  0.734  0.028  0.491  1.0
  O  O40  1  0.266  0.972  0.509  1.0
  O  O41  1  0.621  0.282  0.580  1.0
  O  O42  1  0.379  0.718  0.420  1.0
  O  O43  1  0.510  0.482  0.215  1.0
  O  O44  1  0.490  0.518  0.785  1.0
  O  O45  1  0.436  0.217  0.383  1.0
  O  O46  1  0.564  0.783  0.617  1.0
  O  O47  1  0.362  0.740  0.888  1.0
  O  O48  1  0.638  0.260  0.112  1.0
  O  O49  1  0.330  0.383  0.138  1.0
  O  O50  1  0.670  0.617  0.862  1.0
  O  O51  1  0.401  0.058  0.658  1.0
  O  O52  1  0.599  0.942  0.342  1.0
[/CIF]
.
The material structure described by Cr6CuSi2(Pb5O17)2 crystallizes in the triclinic P-1 space group. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to one O(5), one O(6), one O(7), and one O(8) atom. In the third Cr site, Cr(3) is bonded to one O(10), one O(11), one O(12), and one O(9) atom to form CrO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. Cu(1) is bonded to two equivalent O(11), two equivalent O(14), and two equivalent O(17) atoms to form distorted CuO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra and corners with two equivalent Si(1)O4 tetrahedra. There are five inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 7-coordinate geometry to one O(12), one O(13), one O(15), one O(2), one O(4), one O(5), and one O(7) atom. In the second Pb site, Pb(2) is bonded in a 6-coordinate geometry to one O(12), one O(14), one O(17), one O(2), one O(3), and one O(5) atom. In the third Pb site, Pb(3) is bonded in a distorted pentagonal planar geometry to one O(11), one O(15), one O(17), one O(3), and one O(7) atom. In the fourth Pb site, Pb(4) is bonded in a 5-coordinate geometry to one O(1), one O(10), one O(11), one O(16), and one O(8) atom. In the fifth Pb site, Pb(5) is bonded in a 5-coordinate geometry to one O(10), one O(13), one O(15), one O(16), and one O(5) atom. Si(1) is bonded to one O(13), one O(14), one O(15), and one O(16) atom to form SiO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are seventeen inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Cr(1) and one Pb(4) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Cr(1), one Pb(1), and one Pb(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Cr(1), one Pb(2), and one Pb(3) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Cr(1) and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Cr(2), one Pb(1), one Pb(2), and one Pb(5) atom. In the sixth O site, O(6) is bonded in a single-bond geometry to one Cr(2) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Cr(2), one Pb(1), and one Pb(3) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to one Cr(2) and one Pb(4) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one Cr(3) atom. In the tenth O site, O(10) is bonded in a single-bond geometry to one Cr(3), one Pb(4), and one Pb(5) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Cr(3), one Cu(1), one Pb(3), and one Pb(4) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Cr(3), one Pb(1), and one Pb(2) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal non-coplanar geometry to one Pb(1), one Pb(5), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 3-coordinate geometry to one Cu(1), one Pb(2), and one Si(1) atom. In the fifteenth O site, O(15) is bonded in a distorted single-bond geometry to one Pb(1), one Pb(3), one Pb(5), and one Si(1) atom. In the sixteenth O site, O(16) is bonded in a distorted single-bond geometry to one Pb(4), one Pb(5), and one Si(1) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Cu(1), one Pb(2), and one Pb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cr6CuSi2(Pb5O17)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.797
_cell_length_b   10.110
_cell_length_c   10.117
_cell_angle_alpha   65.070
_cell_angle_beta   71.670
_cell_angle_gamma   68.369
_symmetry_Int_Tables_number   1
_cell_volume   829.495
_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
  Cr  Cr0  1  0.034  0.645  0.279  1.0
  Cr  Cr1  1  0.966  0.355  0.721  1.0
  Cr  Cr2  1  0.735  0.846  0.982  1.0
  Cr  Cr3  1  0.265  0.154  0.018  1.0
  Cr  Cr4  1  0.777  0.165  0.512  1.0
  Cr  Cr5  1  0.223  0.835  0.488  1.0
  Cu  Cu6  1  0.500  0.000  0.500  1.0
  Si  Si7  1  0.479  0.334  0.208  1.0
  Si  Si8  1  0.521  0.666  0.792  1.0
  Pb  Pb9  1  0.365  0.739  0.156  1.0
  Pb  Pb10  1  0.635  0.261  0.844  1.0
  Pb  Pb11  1  0.355  0.332  0.574  1.0
  Pb  Pb12  1  0.645  0.668  0.426  1.0
  Pb  Pb13  1  0.182  0.972  0.785  1.0
  Pb  Pb14  1  0.818  0.028  0.215  1.0
  Pb  Pb15  1  0.144  0.253  0.327  1.0
  Pb  Pb16  1  0.856  0.747  0.673  1.0
  Pb  Pb17  1  0.763  0.468  0.083  1.0
  Pb  Pb18  1  0.237  0.532  0.917  1.0
  O  O19  1  0.983  0.518  0.254  1.0
  O  O20  1  0.017  0.482  0.746  1.0
  O  O21  1  0.181  0.561  0.362  1.0
  O  O22  1  0.819  0.439  0.638  1.0
  O  O23  1  0.115  0.264  0.619  1.0
  O  O24  1  0.885  0.736  0.381  1.0
  O  O25  1  0.083  0.772  0.118  1.0
  O  O26  1  0.917  0.228  0.882  1.0
  O  O27  1  0.644  0.729  0.133  1.0
  O  O28  1  0.356  0.271  0.867  1.0
  O  O29  1  0.631  0.945  0.856  1.0
  O  O30  1  0.369  0.055  0.144  1.0
  O  O31  1  0.779  0.965  0.026  1.0
  O  O32  1  0.221  0.035  0.974  1.0
  O  O33  1  0.889  0.732  0.911  1.0
  O  O34  1  0.111  0.268  0.089  1.0
  O  O35  1  0.893  0.087  0.627  1.0
  O  O36  1  0.107  0.913  0.373  1.0
  O  O37  1  0.858  0.260  0.345  1.0
  O  O38  1  0.142  0.740  0.655  1.0
  O  O39  1  0.734  0.028  0.491  1.0
  O  O40  1  0.266  0.972  0.509  1.0
  O  O41  1  0.621  0.282  0.580  1.0
  O  O42  1  0.379  0.718  0.420  1.0
  O  O43  1  0.510  0.482  0.215  1.0
  O  O44  1  0.490  0.518  0.785  1.0
  O  O45  1  0.436  0.217  0.383  1.0
  O  O46  1  0.564  0.783  0.617  1.0
  O  O47  1  0.362  0.740  0.888  1.0
  O  O48  1  0.638  0.260  0.112  1.0
  O  O49  1  0.330  0.383  0.138  1.0
  O  O50  1  0.670  0.617  0.862  1.0
  O  O51  1  0.401  0.058  0.658  1.0
  O  O52  1  0.599  0.942  0.342  1.0
[/CIF]
.