The material structure described by Rb2Cr2O7 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 9-coordinate geometry to one O(2), one O(4), one O(5), two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(2) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(5), one O(6), and one O(7) atom to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing CrO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Rb(1), one Rb(2), and one Cr(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Rb(2), one Cr(1), and one Cr(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.391
_cell_length_b   7.566
_cell_length_c   7.818
_cell_angle_alpha   109.791
_cell_angle_beta   91.264
_cell_angle_gamma   108.682
_symmetry_Int_Tables_number   1
_cell_volume   385.518
_cell_formula_units_Z   2
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  0.385  0.991  0.747  1.0
  Rb  Rb1  1  0.615  0.009  0.253  1.0
  Rb  Rb2  1  0.189  0.411  0.253  1.0
  Rb  Rb3  1  0.811  0.589  0.747  1.0
  Cr  Cr4  1  0.300  0.478  0.755  1.0
  Cr  Cr5  1  0.919  0.124  0.776  1.0
  Cr  Cr6  1  0.081  0.876  0.224  1.0
  Cr  Cr7  1  0.700  0.522  0.245  1.0
  O  O8  1  0.235  0.841  0.349  1.0
  O  O9  1  0.811  0.435  0.359  1.0
  O  O10  1  0.174  0.915  0.049  1.0
  O  O11  1  0.826  0.085  0.951  1.0
  O  O12  1  0.022  0.064  0.341  1.0
  O  O13  1  0.601  0.665  0.382  1.0
  O  O14  1  0.534  0.338  0.089  1.0
  O  O15  1  0.978  0.936  0.659  1.0
  O  O16  1  0.189  0.565  0.641  1.0
  O  O17  1  0.765  0.159  0.651  1.0
  O  O18  1  0.869  0.659  0.137  1.0
  O  O19  1  0.466  0.662  0.911  1.0
  O  O20  1  0.131  0.341  0.863  1.0
  O  O21  1  0.399  0.335  0.618  1.0
[/CIF]
.
The material structure described by Rb2Cr2O7 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 9-coordinate geometry to one O(2), one O(4), one O(5), two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms. In the second Rb site, Rb(2) is bonded in a 8-coordinate geometry to one O(1), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(2) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(5), one O(6), and one O(7) atom to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form corner-sharing CrO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(2) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Rb(1), one Rb(2), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one Rb(1), one Rb(2), and one Cr(1) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Rb(2), two equivalent Rb(1), and one Cr(1) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Rb(2), one Cr(1), and one Cr(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2Cr2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.391
_cell_length_b   7.566
_cell_length_c   7.818
_cell_angle_alpha   109.791
_cell_angle_beta   91.264
_cell_angle_gamma   108.682
_symmetry_Int_Tables_number   1
_cell_volume   385.518
_cell_formula_units_Z   2
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  0.385  0.991  0.747  1.0
  Rb  Rb1  1  0.615  0.009  0.253  1.0
  Rb  Rb2  1  0.189  0.411  0.253  1.0
  Rb  Rb3  1  0.811  0.589  0.747  1.0
  Cr  Cr4  1  0.300  0.478  0.755  1.0
  Cr  Cr5  1  0.919  0.124  0.776  1.0
  Cr  Cr6  1  0.081  0.876  0.224  1.0
  Cr  Cr7  1  0.700  0.522  0.245  1.0
  O  O8  1  0.235  0.841  0.349  1.0
  O  O9  1  0.811  0.435  0.359  1.0
  O  O10  1  0.174  0.915  0.049  1.0
  O  O11  1  0.826  0.085  0.951  1.0
  O  O12  1  0.022  0.064  0.341  1.0
  O  O13  1  0.601  0.665  0.382  1.0
  O  O14  1  0.534  0.338  0.089  1.0
  O  O15  1  0.978  0.936  0.659  1.0
  O  O16  1  0.189  0.565  0.641  1.0
  O  O17  1  0.765  0.159  0.651  1.0
  O  O18  1  0.869  0.659  0.137  1.0
  O  O19  1  0.466  0.662  0.911  1.0
  O  O20  1  0.131  0.341  0.863  1.0
  O  O21  1  0.399  0.335  0.618  1.0
[/CIF]
.