The crystal structure described by Li2Mn2Si2O7 crystallizes in the orthorhombic Ama2 space group. Li(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with four equivalent Si(1)O4 tetrahedra, corners with two equivalent Mn(2)O5 trigonal bipyramids, and corners with two equivalent Li(1)O4 trigonal pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MnO5 trigonal bipyramids that share corners with six equivalent Si(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with three equivalent Mn(2)O5 trigonal bipyramids, and corners with four equivalent Li(1)O4 trigonal pyramids. There are four inequivalent O sites. In the first O site, O(4) is bonded to two equivalent Li(1), one Mn(1), and one Si(1) atom to form distorted OLi2MnSi tetrahedra that share corners with three equivalent O(4)Li2MnSi tetrahedra and corners with five equivalent O(3)LiMn2Si tetrahedra. In the second O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2) and two equivalent Si(1) atoms. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Li(1), one Mn(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(3) is bonded to one Li(1), one Mn(1), one Mn(2), and one Si(1) atom to form distorted OLiMn2Si tetrahedra that share corners with two equivalent O(3)LiMn2Si tetrahedra and corners with five equivalent O(4)Li2MnSi tetrahedra. is represented by the CIF card [CIF]
data_Li2Mn2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.010
_cell_length_b   13.369
_cell_length_c   5.010
_cell_angle_alpha   89.999
_cell_angle_beta   61.209
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   294.084
_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
  Li  Li0  1  0.246  0.582  0.346  1.0
  Li  Li1  1  0.246  0.918  0.346  1.0
  Li  Li2  1  0.654  0.418  0.754  1.0
  Li  Li3  1  0.654  0.082  0.754  1.0
  Mn  Mn4  1  0.972  1.000  0.028  1.0
  Mn  Mn5  1  0.972  0.500  0.028  1.0
  Mn  Mn6  1  0.998  0.250  0.037  1.0
  Mn  Mn7  1  0.963  0.750  0.002  1.0
  Si  Si8  1  0.309  0.363  0.405  1.0
  Si  Si9  1  0.309  0.137  0.404  1.0
  Si  Si10  1  0.596  0.637  0.691  1.0
  Si  Si11  1  0.596  0.863  0.691  1.0
  O  O12  1  0.164  0.250  0.382  1.0
  O  O13  1  0.618  0.750  0.836  1.0
  O  O14  1  0.663  0.134  0.131  1.0
  O  O15  1  0.663  0.366  0.131  1.0
  O  O16  1  0.869  0.866  0.337  1.0
  O  O17  1  0.869  0.634  0.337  1.0
  O  O18  1  0.260  0.871  0.709  1.0
  O  O19  1  0.260  0.629  0.709  1.0
  O  O20  1  0.291  0.371  0.740  1.0
  O  O21  1  0.291  0.129  0.740  1.0
  O  O22  1  0.078  0.057  0.383  1.0
  O  O23  1  0.078  0.443  0.383  1.0
  O  O24  1  0.617  0.557  0.923  1.0
  O  O25  1  0.617  0.943  0.922  1.0
[/CIF]
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The crystal structure described by Li2Mn2Si2O7 crystallizes in the orthorhombic Ama2 space group. Li(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with four equivalent Si(1)O4 tetrahedra, corners with two equivalent Mn(2)O5 trigonal bipyramids, and corners with two equivalent Li(1)O4 trigonal pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second Mn site, Mn(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MnO5 trigonal bipyramids that share corners with six equivalent Si(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with three equivalent Mn(2)O5 trigonal bipyramids, and corners with four equivalent Li(1)O4 trigonal pyramids. There are four inequivalent O sites. In the first O site, O(4) is bonded to two equivalent Li(1), one Mn(1), and one Si(1) atom to form distorted OLi2MnSi tetrahedra that share corners with three equivalent O(4)Li2MnSi tetrahedra and corners with five equivalent O(3)LiMn2Si tetrahedra. In the second O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mn(2) and two equivalent Si(1) atoms. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Li(1), one Mn(1), one Mn(2), and one Si(1) atom. In the fourth O site, O(3) is bonded to one Li(1), one Mn(1), one Mn(2), and one Si(1) atom to form distorted OLiMn2Si tetrahedra that share corners with two equivalent O(3)LiMn2Si tetrahedra and corners with five equivalent O(4)Li2MnSi tetrahedra. is represented by the CIF card [CIF]
data_Li2Mn2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.010
_cell_length_b   13.369
_cell_length_c   5.010
_cell_angle_alpha   89.999
_cell_angle_beta   61.209
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   294.084
_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
  Li  Li0  1  0.246  0.582  0.346  1.0
  Li  Li1  1  0.246  0.918  0.346  1.0
  Li  Li2  1  0.654  0.418  0.754  1.0
  Li  Li3  1  0.654  0.082  0.754  1.0
  Mn  Mn4  1  0.972  1.000  0.028  1.0
  Mn  Mn5  1  0.972  0.500  0.028  1.0
  Mn  Mn6  1  0.998  0.250  0.037  1.0
  Mn  Mn7  1  0.963  0.750  0.002  1.0
  Si  Si8  1  0.309  0.363  0.405  1.0
  Si  Si9  1  0.309  0.137  0.404  1.0
  Si  Si10  1  0.596  0.637  0.691  1.0
  Si  Si11  1  0.596  0.863  0.691  1.0
  O  O12  1  0.164  0.250  0.382  1.0
  O  O13  1  0.618  0.750  0.836  1.0
  O  O14  1  0.663  0.134  0.131  1.0
  O  O15  1  0.663  0.366  0.131  1.0
  O  O16  1  0.869  0.866  0.337  1.0
  O  O17  1  0.869  0.634  0.337  1.0
  O  O18  1  0.260  0.871  0.709  1.0
  O  O19  1  0.260  0.629  0.709  1.0
  O  O20  1  0.291  0.371  0.740  1.0
  O  O21  1  0.291  0.129  0.740  1.0
  O  O22  1  0.078  0.057  0.383  1.0
  O  O23  1  0.078  0.443  0.383  1.0
  O  O24  1  0.617  0.557  0.923  1.0
  O  O25  1  0.617  0.943  0.922  1.0
[/CIF]
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