The structure described by Sr2MnGe2O7 crystallizes in the tetragonal P-42_1m space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(2), and four equivalent O(3) atoms. Mn(1) is bonded to four equivalent O(3) atoms to form MnO4 tetrahedra that share corners with four equivalent Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form GeO4 tetrahedra that share  a cornercorner with one Ge(1)O4 tetrahedra and corners with two equivalent Mn(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Ge(1) atoms to form a mixture of distorted corner and edge-sharing OSr2Ge2 tetrahedra. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Ge(1) atom to form distorted OSr3Ge tetrahedra that share corners with two equivalent O(1)Sr2Ge2 tetrahedra, corners with four equivalent O(2)Sr3Ge tetrahedra,  an edgeedge with one O(1)Sr2Ge2 tetrahedra, and  an edgeedge with one O(2)Sr3Ge tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Mn(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Sr2MnGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.389
_cell_length_b   8.393
_cell_length_c   8.393
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   379.643
_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
  Ge  Ge0  1  0.943  0.141  0.359  1.0
  Ge  Ge1  1  0.057  0.641  0.141  1.0
  Ge  Ge2  1  0.943  0.859  0.641  1.0
  Ge  Ge3  1  0.057  0.359  0.859  1.0
  Mn  Mn4  1  1.000  0.500  0.500  1.0
  Mn  Mn5  1  1.000  1.000  1.000  1.0
  O  O6  1  0.190  0.500  0.000  1.0
  O  O7  1  0.810  1.000  0.500  1.0
  O  O8  1  0.267  0.139  0.361  1.0
  O  O9  1  0.733  0.639  0.139  1.0
  O  O10  1  0.267  0.861  0.639  1.0
  O  O11  1  0.733  0.361  0.861  1.0
  O  O12  1  0.217  0.581  0.316  1.0
  O  O13  1  0.783  0.081  0.184  1.0
  O  O14  1  0.217  0.419  0.684  1.0
  O  O15  1  0.783  0.919  0.816  1.0
  O  O16  1  0.783  0.684  0.581  1.0
  O  O17  1  0.217  0.184  0.919  1.0
  O  O18  1  0.783  0.316  0.419  1.0
  O  O19  1  0.217  0.816  0.081  1.0
  Sr  Sr20  1  0.506  0.667  0.833  1.0
  Sr  Sr21  1  0.494  0.167  0.667  1.0
  Sr  Sr22  1  0.506  0.333  0.167  1.0
  Sr  Sr23  1  0.494  0.833  0.333  1.0
[/CIF]
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The structure described by Sr2MnGe2O7 crystallizes in the tetragonal P-42_1m space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(2), and four equivalent O(3) atoms. Mn(1) is bonded to four equivalent O(3) atoms to form MnO4 tetrahedra that share corners with four equivalent Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form GeO4 tetrahedra that share  a cornercorner with one Ge(1)O4 tetrahedra and corners with two equivalent Mn(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Ge(1) atoms to form a mixture of distorted corner and edge-sharing OSr2Ge2 tetrahedra. In the second O site, O(2) is bonded to three equivalent Sr(1) and one Ge(1) atom to form distorted OSr3Ge tetrahedra that share corners with two equivalent O(1)Sr2Ge2 tetrahedra, corners with four equivalent O(2)Sr3Ge tetrahedra,  an edgeedge with one O(1)Sr2Ge2 tetrahedra, and  an edgeedge with one O(2)Sr3Ge tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Mn(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Sr2MnGe2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.389
_cell_length_b   8.393
_cell_length_c   8.393
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   379.643
_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
  Ge  Ge0  1  0.943  0.141  0.359  1.0
  Ge  Ge1  1  0.057  0.641  0.141  1.0
  Ge  Ge2  1  0.943  0.859  0.641  1.0
  Ge  Ge3  1  0.057  0.359  0.859  1.0
  Mn  Mn4  1  1.000  0.500  0.500  1.0
  Mn  Mn5  1  1.000  1.000  1.000  1.0
  O  O6  1  0.190  0.500  0.000  1.0
  O  O7  1  0.810  1.000  0.500  1.0
  O  O8  1  0.267  0.139  0.361  1.0
  O  O9  1  0.733  0.639  0.139  1.0
  O  O10  1  0.267  0.861  0.639  1.0
  O  O11  1  0.733  0.361  0.861  1.0
  O  O12  1  0.217  0.581  0.316  1.0
  O  O13  1  0.783  0.081  0.184  1.0
  O  O14  1  0.217  0.419  0.684  1.0
  O  O15  1  0.783  0.919  0.816  1.0
  O  O16  1  0.783  0.684  0.581  1.0
  O  O17  1  0.217  0.184  0.919  1.0
  O  O18  1  0.783  0.316  0.419  1.0
  O  O19  1  0.217  0.816  0.081  1.0
  Sr  Sr20  1  0.506  0.667  0.833  1.0
  Sr  Sr21  1  0.494  0.167  0.667  1.0
  Sr  Sr22  1  0.506  0.333  0.167  1.0
  Sr  Sr23  1  0.494  0.833  0.333  1.0
[/CIF]
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