The compound described by CaNiGe2O6 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. Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent Ge(1)O4 tetrahedra and edges with two equivalent Ni(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 Ni(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 Ni(1), and one Ge(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent Ni(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OCaNi2Ge tetrahedra. is represented by the CIF card [CIF]
data_CaNi(GeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.478
_cell_length_b   6.832
_cell_length_c   6.832
_cell_angle_alpha   83.033
_cell_angle_beta   78.434
_cell_angle_gamma   78.435
_symmetry_Int_Tables_number   1
_cell_volume   244.514
_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  0.250  0.302  0.698  1.0
  Ca  Ca1  1  0.750  0.698  0.302  1.0
  Ge  Ge2  1  0.220  0.814  0.617  1.0
  Ge  Ge3  1  0.280  0.383  0.186  1.0
  Ge  Ge4  1  0.780  0.186  0.383  1.0
  Ge  Ge5  1  0.720  0.617  0.814  1.0
  Ni  Ni6  1  0.250  0.911  0.089  1.0
  Ni  Ni7  1  0.750  0.089  0.911  1.0
  O  O8  1  0.477  0.609  0.671  1.0
  O  O9  1  0.023  0.329  0.391  1.0
  O  O10  1  0.523  0.391  0.329  1.0
  O  O11  1  0.977  0.671  0.609  1.0
  O  O12  1  0.840  0.374  0.898  1.0
  O  O13  1  0.660  0.102  0.626  1.0
  O  O14  1  0.160  0.626  0.102  1.0
  O  O15  1  0.340  0.898  0.374  1.0
  O  O16  1  0.133  0.983  0.803  1.0
  O  O17  1  0.367  0.197  0.017  1.0
  O  O18  1  0.867  0.017  0.197  1.0
  O  O19  1  0.633  0.803  0.983  1.0
[/CIF]
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The compound described by CaNiGe2O6 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. Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent Ge(1)O4 tetrahedra and edges with two equivalent Ni(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 Ni(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 Ni(1), and one Ge(1) atom. In the third O site, O(3) is bonded to one Ca(1), two equivalent Ni(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OCaNi2Ge tetrahedra. is represented by the CIF card [CIF]
data_CaNi(GeO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.478
_cell_length_b   6.832
_cell_length_c   6.832
_cell_angle_alpha   83.033
_cell_angle_beta   78.434
_cell_angle_gamma   78.435
_symmetry_Int_Tables_number   1
_cell_volume   244.514
_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  0.250  0.302  0.698  1.0
  Ca  Ca1  1  0.750  0.698  0.302  1.0
  Ge  Ge2  1  0.220  0.814  0.617  1.0
  Ge  Ge3  1  0.280  0.383  0.186  1.0
  Ge  Ge4  1  0.780  0.186  0.383  1.0
  Ge  Ge5  1  0.720  0.617  0.814  1.0
  Ni  Ni6  1  0.250  0.911  0.089  1.0
  Ni  Ni7  1  0.750  0.089  0.911  1.0
  O  O8  1  0.477  0.609  0.671  1.0
  O  O9  1  0.023  0.329  0.391  1.0
  O  O10  1  0.523  0.391  0.329  1.0
  O  O11  1  0.977  0.671  0.609  1.0
  O  O12  1  0.840  0.374  0.898  1.0
  O  O13  1  0.660  0.102  0.626  1.0
  O  O14  1  0.160  0.626  0.102  1.0
  O  O15  1  0.340  0.898  0.374  1.0
  O  O16  1  0.133  0.983  0.803  1.0
  O  O17  1  0.367  0.197  0.017  1.0
  O  O18  1  0.867  0.017  0.197  1.0
  O  O19  1  0.633  0.803  0.983  1.0
[/CIF]
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