The material structure described by KTb(CO3)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(2) atoms. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Tb(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent K(1), one Tb(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1), two equivalent Tb(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KTb(CO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.446
_cell_length_b   6.446
_cell_length_c   6.984
_cell_angle_alpha   76.205
_cell_angle_beta   76.205
_cell_angle_gamma   96.393
_symmetry_Int_Tables_number   1
_cell_volume   269.262
_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  0.620  0.380  0.750  1.0
  K  K1  1  0.380  0.620  0.250  1.0
  Tb  Tb2  1  0.096  0.904  0.750  1.0
  Tb  Tb3  1  0.904  0.096  0.250  1.0
  C  C4  1  0.645  0.890  0.758  1.0
  C  C5  1  0.355  0.110  0.242  1.0
  C  C6  1  0.110  0.355  0.742  1.0
  C  C7  1  0.890  0.645  0.258  1.0
  O  O8  1  0.444  0.896  0.780  1.0
  O  O9  1  0.556  0.104  0.220  1.0
  O  O10  1  0.104  0.556  0.720  1.0
  O  O11  1  0.896  0.444  0.280  1.0
  O  O12  1  0.714  0.749  0.883  1.0
  O  O13  1  0.286  0.251  0.117  1.0
  O  O14  1  0.251  0.286  0.617  1.0
  O  O15  1  0.749  0.714  0.383  1.0
  O  O16  1  0.796  0.033  0.609  1.0
  O  O17  1  0.204  0.967  0.391  1.0
  O  O18  1  0.967  0.204  0.891  1.0
  O  O19  1  0.033  0.796  0.109  1.0
[/CIF]
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The material structure described by KTb(CO3)2 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(2) atoms. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), and four equivalent O(3) atoms. C(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Tb(1) and one C(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent K(1), one Tb(1), and one C(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one K(1), two equivalent Tb(1), and one C(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_KTb(CO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.446
_cell_length_b   6.446
_cell_length_c   6.984
_cell_angle_alpha   76.205
_cell_angle_beta   76.205
_cell_angle_gamma   96.393
_symmetry_Int_Tables_number   1
_cell_volume   269.262
_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  0.620  0.380  0.750  1.0
  K  K1  1  0.380  0.620  0.250  1.0
  Tb  Tb2  1  0.096  0.904  0.750  1.0
  Tb  Tb3  1  0.904  0.096  0.250  1.0
  C  C4  1  0.645  0.890  0.758  1.0
  C  C5  1  0.355  0.110  0.242  1.0
  C  C6  1  0.110  0.355  0.742  1.0
  C  C7  1  0.890  0.645  0.258  1.0
  O  O8  1  0.444  0.896  0.780  1.0
  O  O9  1  0.556  0.104  0.220  1.0
  O  O10  1  0.104  0.556  0.720  1.0
  O  O11  1  0.896  0.444  0.280  1.0
  O  O12  1  0.714  0.749  0.883  1.0
  O  O13  1  0.286  0.251  0.117  1.0
  O  O14  1  0.251  0.286  0.617  1.0
  O  O15  1  0.749  0.714  0.383  1.0
  O  O16  1  0.796  0.033  0.609  1.0
  O  O17  1  0.204  0.967  0.391  1.0
  O  O18  1  0.967  0.204  0.891  1.0
  O  O19  1  0.033  0.796  0.109  1.0
[/CIF]
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