The structure described by K2Cu(CO3)2 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(12), one O(4), one O(6), one O(9), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(12), one O(2), one O(3), one O(5), and two equivalent O(6) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(8), one O(9), and two equivalent O(7) atoms. In the fourth K site, K(4) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(12), one O(4), one O(7), one O(9), and two equivalent O(8) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(7), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(5), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(10), one O(2), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(11), one O(3), and one O(7) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(12), one O(4), and one O(8) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), one K(4), one Cu(1), and one C(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(2), one K(3), one Cu(1), and one C(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(2), one K(3), one Cu(2), and one C(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(4), one Cu(2), and one C(4) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(2), two equivalent K(1), one Cu(2), and one C(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one K(1), two equivalent K(2), one Cu(2), and one C(2) atom. In the seventh O site, O(7) is bonded in a 1-coordinate geometry to one K(4), two equivalent K(3), one Cu(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one K(3), two equivalent K(4), one Cu(1), and one C(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one K(1), one K(3), one K(4), and one C(1) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one K(2), one K(3), one K(4), and one C(2) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(3), and one C(3) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(4), and one C(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Cu(CO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.667
_cell_length_b   9.476
_cell_length_c   6.596
_cell_angle_alpha   81.017
_cell_angle_beta   61.336
_cell_angle_gamma   37.647
_symmetry_Int_Tables_number   1
_cell_volume   324.731
_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
  K  K0  1  0.576  0.020  0.583  1.0
  K  K1  1  0.806  0.591  0.029  1.0
  K  K2  1  0.661  0.434  0.682  1.0
  K  K3  1  0.220  0.677  0.432  1.0
  Cu  Cu4  1  0.996  0.999  0.006  1.0
  Cu  Cu5  1  0.250  0.254  0.245  1.0
  C  C6  1  0.168  0.577  0.999  1.0
  C  C7  1  0.256  0.997  0.577  1.0
  C  C8  1  0.251  0.997  0.094  1.0
  C  C9  1  0.660  0.090  0.997  1.0
  O  O10  1  0.993  0.817  0.164  1.0
  O  O11  1  0.020  0.172  0.815  1.0
  O  O12  1  0.094  0.217  0.242  1.0
  O  O13  1  0.448  0.242  0.221  1.0
  O  O14  1  0.102  0.496  0.097  1.0
  O  O15  1  0.313  0.088  0.480  1.0
  O  O16  1  0.157  0.948  0.141  1.0
  O  O17  1  0.756  0.145  0.949  1.0
  O  O18  1  0.352  0.471  0.767  1.0
  O  O19  1  0.402  0.772  0.473  1.0
  O  O20  1  0.470  0.855  0.909  1.0
  O  O21  1  0.780  0.902  0.838  1.0
[/CIF]
.
The structure described by K2Cu(CO3)2 crystallizes in the triclinic P1 space group. There are four inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to one O(1), one O(11), one O(12), one O(4), one O(6), one O(9), and two equivalent O(5) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(12), one O(2), one O(3), one O(5), and two equivalent O(6) atoms. In the third K site, K(3) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(8), one O(9), and two equivalent O(7) atoms. In the fourth K site, K(4) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(12), one O(4), one O(7), one O(9), and two equivalent O(8) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(7), and one O(8) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are four inequivalent C sites. In the first C site, C(1) is bonded in a trigonal planar geometry to one O(1), one O(5), and one O(9) atom. In the second C site, C(2) is bonded in a trigonal planar geometry to one O(10), one O(2), and one O(6) atom. In the third C site, C(3) is bonded in a trigonal planar geometry to one O(11), one O(3), and one O(7) atom. In the fourth C site, C(4) is bonded in a trigonal planar geometry to one O(12), one O(4), and one O(8) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(1), one K(4), one Cu(1), and one C(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(2), one K(3), one Cu(1), and one C(2) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(2), one K(3), one Cu(2), and one C(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one K(1), one K(4), one Cu(2), and one C(4) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one K(2), two equivalent K(1), one Cu(2), and one C(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one K(1), two equivalent K(2), one Cu(2), and one C(2) atom. In the seventh O site, O(7) is bonded in a 1-coordinate geometry to one K(4), two equivalent K(3), one Cu(1), and one C(3) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one K(3), two equivalent K(4), one Cu(1), and one C(4) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one K(1), one K(3), one K(4), and one C(1) atom. In the tenth O site, O(10) is bonded in a distorted single-bond geometry to one K(2), one K(3), one K(4), and one C(2) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(3), and one C(3) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one K(1), one K(2), one K(4), and one C(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Cu(CO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.667
_cell_length_b   9.476
_cell_length_c   6.596
_cell_angle_alpha   81.017
_cell_angle_beta   61.336
_cell_angle_gamma   37.647
_symmetry_Int_Tables_number   1
_cell_volume   324.731
_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
  K  K0  1  0.576  0.020  0.583  1.0
  K  K1  1  0.806  0.591  0.029  1.0
  K  K2  1  0.661  0.434  0.682  1.0
  K  K3  1  0.220  0.677  0.432  1.0
  Cu  Cu4  1  0.996  0.999  0.006  1.0
  Cu  Cu5  1  0.250  0.254  0.245  1.0
  C  C6  1  0.168  0.577  0.999  1.0
  C  C7  1  0.256  0.997  0.577  1.0
  C  C8  1  0.251  0.997  0.094  1.0
  C  C9  1  0.660  0.090  0.997  1.0
  O  O10  1  0.993  0.817  0.164  1.0
  O  O11  1  0.020  0.172  0.815  1.0
  O  O12  1  0.094  0.217  0.242  1.0
  O  O13  1  0.448  0.242  0.221  1.0
  O  O14  1  0.102  0.496  0.097  1.0
  O  O15  1  0.313  0.088  0.480  1.0
  O  O16  1  0.157  0.948  0.141  1.0
  O  O17  1  0.756  0.145  0.949  1.0
  O  O18  1  0.352  0.471  0.767  1.0
  O  O19  1  0.402  0.772  0.473  1.0
  O  O20  1  0.470  0.855  0.909  1.0
  O  O21  1  0.780  0.902  0.838  1.0
[/CIF]
.