The structure described by Rb4CuSi2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Rb(2), two equivalent Rb(1), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Cu(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4CuSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.373
_cell_length_b   7.220
_cell_length_c   7.296
_cell_angle_alpha   114.548
_cell_angle_beta   100.233
_cell_angle_gamma   108.120
_symmetry_Int_Tables_number   1
_cell_volume   271.314
_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
  Rb  Rb0  1  0.322  0.077  0.715  1.0
  Rb  Rb1  1  0.678  0.923  0.285  1.0
  Rb  Rb2  1  0.931  0.457  0.222  1.0
  Rb  Rb3  1  0.069  0.543  0.778  1.0
  Cu  Cu4  1  0.500  0.500  0.500  1.0
  Si  Si5  1  0.215  0.080  0.223  1.0
  Si  Si6  1  0.785  0.920  0.777  1.0
  O  O7  1  0.473  0.241  0.232  1.0
  O  O8  1  0.817  0.731  0.567  1.0
  O  O9  1  0.183  0.269  0.433  1.0
  O  O10  1  0.798  0.141  0.766  1.0
  O  O11  1  0.202  0.859  0.234  1.0
  O  O12  1  0.527  0.759  0.768  1.0
  O  O13  1  0.000  0.000  0.000  1.0
[/CIF]
.
The structure described by Rb4CuSi2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the second Rb site, Rb(2) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Rb(2), two equivalent Rb(1), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Rb(1), two equivalent Rb(2), one Cu(1), and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Rb(1), two equivalent Rb(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to two equivalent Rb(1), two equivalent Rb(2), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4CuSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.373
_cell_length_b   7.220
_cell_length_c   7.296
_cell_angle_alpha   114.548
_cell_angle_beta   100.233
_cell_angle_gamma   108.120
_symmetry_Int_Tables_number   1
_cell_volume   271.314
_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
  Rb  Rb0  1  0.322  0.077  0.715  1.0
  Rb  Rb1  1  0.678  0.923  0.285  1.0
  Rb  Rb2  1  0.931  0.457  0.222  1.0
  Rb  Rb3  1  0.069  0.543  0.778  1.0
  Cu  Cu4  1  0.500  0.500  0.500  1.0
  Si  Si5  1  0.215  0.080  0.223  1.0
  Si  Si6  1  0.785  0.920  0.777  1.0
  O  O7  1  0.473  0.241  0.232  1.0
  O  O8  1  0.817  0.731  0.567  1.0
  O  O9  1  0.183  0.269  0.433  1.0
  O  O10  1  0.798  0.141  0.766  1.0
  O  O11  1  0.202  0.859  0.234  1.0
  O  O12  1  0.527  0.759  0.768  1.0
  O  O13  1  0.000  0.000  0.000  1.0
[/CIF]
.