The structure described by Ag6Si2O7 crystallizes in the monoclinic C2/m space group. There are five inequivalent Ag sites. In the first Ag site, Ag(1) is bonded to one O(1), one O(5), and two equivalent O(2) atoms to form distorted AgO4 tetrahedra that share  a cornercorner with one Ag(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  a cornercorner with one Ag(2)O4 trigonal pyramid, and  an edgeedge with one Ag(1)O4 tetrahedra. In the second Ag site, Ag(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form distorted AgO4 trigonal pyramids that share  a cornercorner with one Ag(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Ag(2)O4 trigonal pyramid. In the third Ag site, Ag(3) is bonded in a linear geometry to one O(3) and one O(6) atom. In the fourth Ag site, Ag(4) is bonded in a distorted linear geometry to one O(1) and one O(2) atom. In the fifth Ag site, Ag(5) is bonded in a 3-coordinate geometry to one O(5) and two equivalent O(4) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(7), one O(8), and two equivalent O(5) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Ag(1)O4 tetrahedra, and corners with two equivalent Ag(2)O4 trigonal pyramids. In the second Si site, Si(2) is bonded to one O(1), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Ag(1)O4 tetrahedra and corners with four equivalent Ag(2)O4 trigonal pyramids. In the third Si site, Si(3) is bonded to one O(3), one O(7), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with four equivalent Ag(1)O4 tetrahedra, and corners with two equivalent Ag(2)O4 trigonal pyramids. There are eight inequivalent O sites. In the first O site, O(8) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Ag(1), two equivalent Ag(4), and one Si(2) atom. In the third O site, O(2) is bonded to one Ag(4), two equivalent Ag(1), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OSiAg3 tetrahedra. In the fourth O site, O(3) is bonded to one Ag(3), two equivalent Ag(2), and one Si(3) atom to form distorted corner-sharing OSiAg3 tetrahedra. In the fifth O site, O(4) is bonded to one Ag(2), two equivalent Ag(5), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OSiAg3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ag(1), one Ag(2), one Ag(5), and one Si(1) atom. In the seventh O site, O(6) is bonded in a 4-coordinate geometry to one Ag(3), two equivalent Ag(2), and one Si(2) atom. In the eighth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF card [CIF]
data_Si2Ag6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.182
_cell_length_b   8.182
_cell_length_c   10.856
_cell_angle_alpha   76.935
_cell_angle_beta   76.935
_cell_angle_gamma   74.670
_symmetry_Int_Tables_number   1
_cell_volume   672.045
_cell_formula_units_Z   3
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
  Si  Si0  1  0.895  0.895  0.127  1.0
  Si  Si1  1  0.105  0.105  0.873  1.0
  Si  Si2  1  0.803  0.803  0.617  1.0
  Si  Si3  1  0.344  0.344  0.872  1.0
  Si  Si4  1  0.197  0.197  0.383  1.0
  Si  Si5  1  0.656  0.656  0.128  1.0
  Ag  Ag6  1  0.725  0.440  0.861  1.0
  Ag  Ag7  1  0.275  0.560  0.139  1.0
  Ag  Ag8  1  0.449  0.104  0.621  1.0
  Ag  Ag9  1  0.541  0.541  0.636  1.0
  Ag  Ag10  1  0.996  0.637  0.865  1.0
  Ag  Ag11  1  0.896  0.551  0.379  1.0
  Ag  Ag12  1  0.860  0.162  0.657  1.0
  Ag  Ag13  1  0.004  0.363  0.135  1.0
  Ag  Ag14  1  0.162  0.860  0.657  1.0
  Ag  Ag15  1  0.551  0.896  0.379  1.0
  Ag  Ag16  1  0.440  0.725  0.861  1.0
  Ag  Ag17  1  0.363  0.004  0.135  1.0
  Ag  Ag18  1  0.459  0.459  0.364  1.0
  Ag  Ag19  1  0.560  0.275  0.139  1.0
  Ag  Ag20  1  0.104  0.449  0.621  1.0
  Ag  Ag21  1  0.838  0.140  0.343  1.0
  Ag  Ag22  1  0.140  0.838  0.343  1.0
  Ag  Ag23  1  0.637  0.996  0.865  1.0
  O  O24  1  0.246  0.246  0.222  1.0
  O  O25  1  0.249  0.525  0.927  1.0
  O  O26  1  0.626  0.626  0.286  1.0
  O  O27  1  0.475  0.751  0.073  1.0
  O  O28  1  0.740  0.014  0.571  1.0
  O  O29  1  0.025  0.753  0.213  1.0
  O  O30  1  0.751  0.475  0.073  1.0
  O  O31  1  0.247  0.975  0.787  1.0
  O  O32  1  0.294  0.294  0.454  1.0
  O  O33  1  0.975  0.247  0.787  1.0
  O  O34  1  0.986  0.260  0.429  1.0
  O  O35  1  0.525  0.249  0.927  1.0
  O  O36  1  0.790  0.790  0.068  1.0
  O  O37  1  0.706  0.706  0.546  1.0
  O  O38  1  0.754  0.754  0.778  1.0
  O  O39  1  0.210  0.210  0.932  1.0
  O  O40  1  0.374  0.374  0.714  1.0
  O  O41  1  0.753  0.025  0.213  1.0
  O  O42  1  0.000  0.000  0.000  1.0
  O  O43  1  0.014  0.740  0.571  1.0
  O  O44  1  0.260  0.986  0.429  1.0
[/CIF]
.
The structure described by Ag6Si2O7 crystallizes in the monoclinic C2/m space group. There are five inequivalent Ag sites. In the first Ag site, Ag(1) is bonded to one O(1), one O(5), and two equivalent O(2) atoms to form distorted AgO4 tetrahedra that share  a cornercorner with one Ag(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra,  a cornercorner with one Ag(2)O4 trigonal pyramid, and  an edgeedge with one Ag(1)O4 tetrahedra. In the second Ag site, Ag(2) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form distorted AgO4 trigonal pyramids that share  a cornercorner with one Ag(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Ag(2)O4 trigonal pyramid. In the third Ag site, Ag(3) is bonded in a linear geometry to one O(3) and one O(6) atom. In the fourth Ag site, Ag(4) is bonded in a distorted linear geometry to one O(1) and one O(2) atom. In the fifth Ag site, Ag(5) is bonded in a 3-coordinate geometry to one O(5) and two equivalent O(4) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(7), one O(8), and two equivalent O(5) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Ag(1)O4 tetrahedra, and corners with two equivalent Ag(2)O4 trigonal pyramids. In the second Si site, Si(2) is bonded to one O(1), one O(6), and two equivalent O(4) atoms to form SiO4 tetrahedra that share corners with two equivalent Ag(1)O4 tetrahedra and corners with four equivalent Ag(2)O4 trigonal pyramids. In the third Si site, Si(3) is bonded to one O(3), one O(7), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with four equivalent Ag(1)O4 tetrahedra, and corners with two equivalent Ag(2)O4 trigonal pyramids. There are eight inequivalent O sites. In the first O site, O(8) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(1) is bonded in a 5-coordinate geometry to two equivalent Ag(1), two equivalent Ag(4), and one Si(2) atom. In the third O site, O(2) is bonded to one Ag(4), two equivalent Ag(1), and one Si(3) atom to form a mixture of distorted corner and edge-sharing OSiAg3 tetrahedra. In the fourth O site, O(3) is bonded to one Ag(3), two equivalent Ag(2), and one Si(3) atom to form distorted corner-sharing OSiAg3 tetrahedra. In the fifth O site, O(4) is bonded to one Ag(2), two equivalent Ag(5), and one Si(2) atom to form a mixture of distorted corner and edge-sharing OSiAg3 tetrahedra. In the sixth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ag(1), one Ag(2), one Ag(5), and one Si(1) atom. In the seventh O site, O(6) is bonded in a 4-coordinate geometry to one Ag(3), two equivalent Ag(2), and one Si(2) atom. In the eighth O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF card [CIF]
data_Si2Ag6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.182
_cell_length_b   8.182
_cell_length_c   10.856
_cell_angle_alpha   76.935
_cell_angle_beta   76.935
_cell_angle_gamma   74.670
_symmetry_Int_Tables_number   1
_cell_volume   672.045
_cell_formula_units_Z   3
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
  Si  Si0  1  0.895  0.895  0.127  1.0
  Si  Si1  1  0.105  0.105  0.873  1.0
  Si  Si2  1  0.803  0.803  0.617  1.0
  Si  Si3  1  0.344  0.344  0.872  1.0
  Si  Si4  1  0.197  0.197  0.383  1.0
  Si  Si5  1  0.656  0.656  0.128  1.0
  Ag  Ag6  1  0.725  0.440  0.861  1.0
  Ag  Ag7  1  0.275  0.560  0.139  1.0
  Ag  Ag8  1  0.449  0.104  0.621  1.0
  Ag  Ag9  1  0.541  0.541  0.636  1.0
  Ag  Ag10  1  0.996  0.637  0.865  1.0
  Ag  Ag11  1  0.896  0.551  0.379  1.0
  Ag  Ag12  1  0.860  0.162  0.657  1.0
  Ag  Ag13  1  0.004  0.363  0.135  1.0
  Ag  Ag14  1  0.162  0.860  0.657  1.0
  Ag  Ag15  1  0.551  0.896  0.379  1.0
  Ag  Ag16  1  0.440  0.725  0.861  1.0
  Ag  Ag17  1  0.363  0.004  0.135  1.0
  Ag  Ag18  1  0.459  0.459  0.364  1.0
  Ag  Ag19  1  0.560  0.275  0.139  1.0
  Ag  Ag20  1  0.104  0.449  0.621  1.0
  Ag  Ag21  1  0.838  0.140  0.343  1.0
  Ag  Ag22  1  0.140  0.838  0.343  1.0
  Ag  Ag23  1  0.637  0.996  0.865  1.0
  O  O24  1  0.246  0.246  0.222  1.0
  O  O25  1  0.249  0.525  0.927  1.0
  O  O26  1  0.626  0.626  0.286  1.0
  O  O27  1  0.475  0.751  0.073  1.0
  O  O28  1  0.740  0.014  0.571  1.0
  O  O29  1  0.025  0.753  0.213  1.0
  O  O30  1  0.751  0.475  0.073  1.0
  O  O31  1  0.247  0.975  0.787  1.0
  O  O32  1  0.294  0.294  0.454  1.0
  O  O33  1  0.975  0.247  0.787  1.0
  O  O34  1  0.986  0.260  0.429  1.0
  O  O35  1  0.525  0.249  0.927  1.0
  O  O36  1  0.790  0.790  0.068  1.0
  O  O37  1  0.706  0.706  0.546  1.0
  O  O38  1  0.754  0.754  0.778  1.0
  O  O39  1  0.210  0.210  0.932  1.0
  O  O40  1  0.374  0.374  0.714  1.0
  O  O41  1  0.753  0.025  0.213  1.0
  O  O42  1  0.000  0.000  0.000  1.0
  O  O43  1  0.014  0.740  0.571  1.0
  O  O44  1  0.260  0.986  0.429  1.0
[/CIF]
.