The crystal structure described by Rb4MgCuSi2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and one O(7) atom. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the fourth Rb site, Rb(4) is bonded in a 6-coordinate geometry to one Cu(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. Mg(1) is bonded in a distorted trigonal planar geometry to one O(2), one O(5), and one O(6) atom. Cu(1) is bonded in a distorted linear geometry to one Rb(4), one O(1), and one O(6) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Rb(1), one Rb(2), one Rb(3), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(3), one Rb(4), one Mg(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Rb(4), one Mg(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Rb(4), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4MgCuSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.199
_cell_length_b   8.327
_cell_length_c   7.246
_cell_angle_alpha   121.330
_cell_angle_beta   104.269
_cell_angle_gamma   96.062
_symmetry_Int_Tables_number   1
_cell_volume   297.002
_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  0.297  0.215  0.829  1.0
  Rb  Rb1  1  0.685  0.927  0.279  1.0
  Rb  Rb2  1  0.833  0.344  0.204  1.0
  Rb  Rb3  1  0.978  0.539  0.807  1.0
  Mg  Mg4  1  0.264  0.770  0.462  1.0
  Cu  Cu5  1  0.455  0.473  0.427  1.0
  Si  Si6  1  0.187  0.083  0.271  1.0
  Si  Si7  1  0.850  0.902  0.743  1.0
  O  O8  1  0.409  0.198  0.252  1.0
  O  O9  1  0.014  0.792  0.595  1.0
  O  O10  1  0.092  0.241  0.460  1.0
  O  O11  1  0.829  0.103  0.766  1.0
  O  O12  1  0.251  0.921  0.325  1.0
  O  O13  1  0.577  0.752  0.625  1.0
  O  O14  1  0.966  0.946  0.008  1.0
[/CIF]
.
The crystal structure described by Rb4MgCuSi2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and one O(5) atom. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and one O(7) atom. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the fourth Rb site, Rb(4) is bonded in a 6-coordinate geometry to one Cu(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. Mg(1) is bonded in a distorted trigonal planar geometry to one O(2), one O(5), and one O(6) atom. Cu(1) is bonded in a distorted linear geometry to one Rb(4), one O(1), and one O(6) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted water-like geometry to one Rb(1), one Rb(2), one Rb(3), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Rb(3), one Rb(4), one Mg(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Si(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Rb(4), one Mg(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Rb(2), one Rb(4), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb4MgCuSi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.199
_cell_length_b   8.327
_cell_length_c   7.246
_cell_angle_alpha   121.330
_cell_angle_beta   104.269
_cell_angle_gamma   96.062
_symmetry_Int_Tables_number   1
_cell_volume   297.002
_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  0.297  0.215  0.829  1.0
  Rb  Rb1  1  0.685  0.927  0.279  1.0
  Rb  Rb2  1  0.833  0.344  0.204  1.0
  Rb  Rb3  1  0.978  0.539  0.807  1.0
  Mg  Mg4  1  0.264  0.770  0.462  1.0
  Cu  Cu5  1  0.455  0.473  0.427  1.0
  Si  Si6  1  0.187  0.083  0.271  1.0
  Si  Si7  1  0.850  0.902  0.743  1.0
  O  O8  1  0.409  0.198  0.252  1.0
  O  O9  1  0.014  0.792  0.595  1.0
  O  O10  1  0.092  0.241  0.460  1.0
  O  O11  1  0.829  0.103  0.766  1.0
  O  O12  1  0.251  0.921  0.325  1.0
  O  O13  1  0.577  0.752  0.625  1.0
  O  O14  1  0.966  0.946  0.008  1.0
[/CIF]
.