The structure described by CaMnGe2O6 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mn(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Ge(1)O4 tetrahedra and edges with two equivalent Mn(1)O6 octahedra. Ge(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with two equivalent Ge(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-60°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Ge(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Mn(1), and one Ge(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent Mn(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OCaMn2Ge trigonal pyramids. is represented by the CIF card [CIF]
data_CaMn(GeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.534
_cell_length_b   6.972
_cell_length_c   6.972
_cell_angle_alpha   83.521
_cell_angle_beta   79.304
_cell_angle_gamma   79.303
_symmetry_Int_Tables_number   1
_cell_volume   258.833
_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
  Ca  Ca0  1  0.750  0.303  0.697  1.0
  Ca  Ca1  1  0.250  0.697  0.303  1.0
  Mn  Mn2  1  0.250  0.092  0.908  1.0
  Mn  Mn3  1  0.750  0.908  0.092  1.0
  Ge  Ge4  1  0.770  0.384  0.189  1.0
  Ge  Ge5  1  0.730  0.811  0.616  1.0
  Ge  Ge6  1  0.230  0.616  0.811  1.0
  Ge  Ge7  1  0.270  0.189  0.384  1.0
  O  O8  1  0.521  0.324  0.391  1.0
  O  O9  1  0.979  0.609  0.676  1.0
  O  O10  1  0.479  0.676  0.609  1.0
  O  O11  1  0.021  0.391  0.324  1.0
  O  O12  1  0.149  0.113  0.622  1.0
  O  O13  1  0.351  0.378  0.887  1.0
  O  O14  1  0.851  0.887  0.378  1.0
  O  O15  1  0.649  0.622  0.113  1.0
  O  O16  1  0.858  0.209  0.018  1.0
  O  O17  1  0.642  0.982  0.791  1.0
  O  O18  1  0.142  0.791  0.982  1.0
  O  O19  1  0.358  0.018  0.209  1.0
[/CIF]
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The structure described by CaMnGe2O6 is Esseneite structured and crystallizes in the monoclinic C2/c space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), and four equivalent O(1) atoms. Mn(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form MnO6 octahedra that share corners with six equivalent Ge(1)O4 tetrahedra and edges with two equivalent Mn(1)O6 octahedra. Ge(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form GeO4 tetrahedra that share corners with three equivalent Mn(1)O6 octahedra and corners with two equivalent Ge(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-60°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ca(1) and two equivalent Ge(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Mn(1), and one Ge(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent Mn(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OCaMn2Ge trigonal pyramids. is represented by the CIF card [CIF]
data_CaMn(GeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.534
_cell_length_b   6.972
_cell_length_c   6.972
_cell_angle_alpha   83.521
_cell_angle_beta   79.304
_cell_angle_gamma   79.303
_symmetry_Int_Tables_number   1
_cell_volume   258.833
_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
  Ca  Ca0  1  0.750  0.303  0.697  1.0
  Ca  Ca1  1  0.250  0.697  0.303  1.0
  Mn  Mn2  1  0.250  0.092  0.908  1.0
  Mn  Mn3  1  0.750  0.908  0.092  1.0
  Ge  Ge4  1  0.770  0.384  0.189  1.0
  Ge  Ge5  1  0.730  0.811  0.616  1.0
  Ge  Ge6  1  0.230  0.616  0.811  1.0
  Ge  Ge7  1  0.270  0.189  0.384  1.0
  O  O8  1  0.521  0.324  0.391  1.0
  O  O9  1  0.979  0.609  0.676  1.0
  O  O10  1  0.479  0.676  0.609  1.0
  O  O11  1  0.021  0.391  0.324  1.0
  O  O12  1  0.149  0.113  0.622  1.0
  O  O13  1  0.351  0.378  0.887  1.0
  O  O14  1  0.851  0.887  0.378  1.0
  O  O15  1  0.649  0.622  0.113  1.0
  O  O16  1  0.858  0.209  0.018  1.0
  O  O17  1  0.642  0.982  0.791  1.0
  O  O18  1  0.142  0.791  0.982  1.0
  O  O19  1  0.358  0.018  0.209  1.0
[/CIF]
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