The structure described by NaTaGeO5 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to one O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted NaO7 pentagonal bipyramids that share corners with four equivalent Ge(1)O4 tetrahedra, edges with four equivalent Ta(1)O6 octahedra, edges with two equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(1)O4 tetrahedra. Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Ge(1)O4 tetrahedra, and edges with four equivalent Na(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. Ge(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 36-51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(1) and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ta(1), and one Ge(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Na(1), one Ta(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_NaTaGeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.703
_cell_length_b   5.703
_cell_length_c   7.518
_cell_angle_alpha   74.722
_cell_angle_beta   74.722
_cell_angle_gamma   104.053
_symmetry_Int_Tables_number   1
_cell_volume   214.337
_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
  Na  Na0  1  0.676  0.324  0.250  1.0
  Na  Na1  1  0.324  0.676  0.750  1.0
  Ta  Ta2  1  0.000  0.000  0.500  1.0
  Ta  Ta3  1  0.000  0.000  0.000  1.0
  Ge  Ge4  1  0.680  0.320  0.750  1.0
  Ge  Ge5  1  0.320  0.680  0.250  1.0
  O  O6  1  0.063  0.937  0.750  1.0
  O  O7  1  0.937  0.063  0.250  1.0
  O  O8  1  0.297  0.881  0.394  1.0
  O  O9  1  0.119  0.703  0.106  1.0
  O  O10  1  0.703  0.119  0.606  1.0
  O  O11  1  0.881  0.297  0.894  1.0
  O  O12  1  0.755  0.640  0.595  1.0
  O  O13  1  0.360  0.245  0.905  1.0
  O  O14  1  0.245  0.360  0.405  1.0
  O  O15  1  0.640  0.755  0.095  1.0
[/CIF]
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The structure described by NaTaGeO5 crystallizes in the monoclinic C2/c space group. Na(1) is bonded to one O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted NaO7 pentagonal bipyramids that share corners with four equivalent Ge(1)O4 tetrahedra, edges with four equivalent Ta(1)O6 octahedra, edges with two equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(1)O4 tetrahedra. Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with four equivalent Ge(1)O4 tetrahedra, and edges with four equivalent Na(1)O7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. Ge(1) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Na(1)O7 pentagonal bipyramids, and  an edgeedge with one Na(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 36-51°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(1) and two equivalent Ta(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ta(1), and one Ge(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Na(1), one Ta(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_NaTaGeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.703
_cell_length_b   5.703
_cell_length_c   7.518
_cell_angle_alpha   74.722
_cell_angle_beta   74.722
_cell_angle_gamma   104.053
_symmetry_Int_Tables_number   1
_cell_volume   214.337
_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
  Na  Na0  1  0.676  0.324  0.250  1.0
  Na  Na1  1  0.324  0.676  0.750  1.0
  Ta  Ta2  1  0.000  0.000  0.500  1.0
  Ta  Ta3  1  0.000  0.000  0.000  1.0
  Ge  Ge4  1  0.680  0.320  0.750  1.0
  Ge  Ge5  1  0.320  0.680  0.250  1.0
  O  O6  1  0.063  0.937  0.750  1.0
  O  O7  1  0.937  0.063  0.250  1.0
  O  O8  1  0.297  0.881  0.394  1.0
  O  O9  1  0.119  0.703  0.106  1.0
  O  O10  1  0.703  0.119  0.606  1.0
  O  O11  1  0.881  0.297  0.894  1.0
  O  O12  1  0.755  0.640  0.595  1.0
  O  O13  1  0.360  0.245  0.905  1.0
  O  O14  1  0.245  0.360  0.405  1.0
  O  O15  1  0.640  0.755  0.095  1.0
[/CIF]
.