The material structure described by Na2Ti2O5 crystallizes in the orthorhombic Pbcn space group. Na(1) is bonded to one O(3) and three equivalent O(2) atoms to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with five equivalent Ti(1)O4 tetrahedra, and  an edgeedge with one Na(1)O4 tetrahedra. Ti(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form TiO4 tetrahedra that share corners with three equivalent Ti(1)O4 tetrahedra and corners with five equivalent Na(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Ti(1) atoms. In the second O site, O(2) is bonded to three equivalent Na(1) and one Ti(1) atom to form a mixture of distorted corner and edge-sharing ONa3Ti trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Na(1) and two equivalent Ti(1) atoms. is represented by the CIF card [CIF]
data_Na2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.499
_cell_length_b   6.601
_cell_length_c   16.334
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   592.909
_cell_formula_units_Z   4
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  0.792  0.098  0.944  1.0
  Na  Na1  1  0.208  0.098  0.444  1.0
  Na  Na2  1  0.292  0.402  0.944  1.0
  Na  Na3  1  0.708  0.402  0.444  1.0
  Na  Na4  1  0.292  0.598  0.556  1.0
  Na  Na5  1  0.708  0.598  0.056  1.0
  Na  Na6  1  0.792  0.902  0.556  1.0
  Na  Na7  1  0.208  0.902  0.056  1.0
  Ti  Ti8  1  0.297  0.102  0.648  1.0
  Ti  Ti9  1  0.703  0.102  0.148  1.0
  Ti  Ti10  1  0.797  0.398  0.648  1.0
  Ti  Ti11  1  0.203  0.398  0.148  1.0
  Ti  Ti12  1  0.203  0.602  0.352  1.0
  Ti  Ti13  1  0.797  0.602  0.852  1.0
  Ti  Ti14  1  0.297  0.898  0.852  1.0
  Ti  Ti15  1  0.703  0.898  0.352  1.0
  O  O16  1  0.232  0.000  0.750  1.0
  O  O17  1  0.768  0.000  0.250  1.0
  O  O18  1  0.212  0.067  0.929  1.0
  O  O19  1  0.788  0.067  0.429  1.0
  O  O20  1  0.625  0.158  0.633  1.0
  O  O21  1  0.375  0.158  0.133  1.0
  O  O22  1  0.125  0.342  0.633  1.0
  O  O23  1  0.875  0.342  0.133  1.0
  O  O24  1  0.712  0.433  0.929  1.0
  O  O25  1  0.288  0.433  0.429  1.0
  O  O26  1  0.732  0.500  0.750  1.0
  O  O27  1  0.268  0.500  0.250  1.0
  O  O28  1  0.712  0.567  0.571  1.0
  O  O29  1  0.288  0.567  0.071  1.0
  O  O30  1  0.125  0.658  0.867  1.0
  O  O31  1  0.875  0.658  0.367  1.0
  O  O32  1  0.625  0.842  0.867  1.0
  O  O33  1  0.375  0.842  0.367  1.0
  O  O34  1  0.212  0.933  0.571  1.0
  O  O35  1  0.788  0.933  0.071  1.0
[/CIF]
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The material structure described by Na2Ti2O5 crystallizes in the orthorhombic Pbcn space group. Na(1) is bonded to one O(3) and three equivalent O(2) atoms to form NaO4 tetrahedra that share corners with four equivalent Na(1)O4 tetrahedra, corners with five equivalent Ti(1)O4 tetrahedra, and  an edgeedge with one Na(1)O4 tetrahedra. Ti(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form TiO4 tetrahedra that share corners with three equivalent Ti(1)O4 tetrahedra and corners with five equivalent Na(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Ti(1) atoms. In the second O site, O(2) is bonded to three equivalent Na(1) and one Ti(1) atom to form a mixture of distorted corner and edge-sharing ONa3Ti trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Na(1) and two equivalent Ti(1) atoms. is represented by the CIF card [CIF]
data_Na2Ti2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.499
_cell_length_b   6.601
_cell_length_c   16.334
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   592.909
_cell_formula_units_Z   4
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  0.792  0.098  0.944  1.0
  Na  Na1  1  0.208  0.098  0.444  1.0
  Na  Na2  1  0.292  0.402  0.944  1.0
  Na  Na3  1  0.708  0.402  0.444  1.0
  Na  Na4  1  0.292  0.598  0.556  1.0
  Na  Na5  1  0.708  0.598  0.056  1.0
  Na  Na6  1  0.792  0.902  0.556  1.0
  Na  Na7  1  0.208  0.902  0.056  1.0
  Ti  Ti8  1  0.297  0.102  0.648  1.0
  Ti  Ti9  1  0.703  0.102  0.148  1.0
  Ti  Ti10  1  0.797  0.398  0.648  1.0
  Ti  Ti11  1  0.203  0.398  0.148  1.0
  Ti  Ti12  1  0.203  0.602  0.352  1.0
  Ti  Ti13  1  0.797  0.602  0.852  1.0
  Ti  Ti14  1  0.297  0.898  0.852  1.0
  Ti  Ti15  1  0.703  0.898  0.352  1.0
  O  O16  1  0.232  0.000  0.750  1.0
  O  O17  1  0.768  0.000  0.250  1.0
  O  O18  1  0.212  0.067  0.929  1.0
  O  O19  1  0.788  0.067  0.429  1.0
  O  O20  1  0.625  0.158  0.633  1.0
  O  O21  1  0.375  0.158  0.133  1.0
  O  O22  1  0.125  0.342  0.633  1.0
  O  O23  1  0.875  0.342  0.133  1.0
  O  O24  1  0.712  0.433  0.929  1.0
  O  O25  1  0.288  0.433  0.429  1.0
  O  O26  1  0.732  0.500  0.750  1.0
  O  O27  1  0.268  0.500  0.250  1.0
  O  O28  1  0.712  0.567  0.571  1.0
  O  O29  1  0.288  0.567  0.071  1.0
  O  O30  1  0.125  0.658  0.867  1.0
  O  O31  1  0.875  0.658  0.367  1.0
  O  O32  1  0.625  0.842  0.867  1.0
  O  O33  1  0.375  0.842  0.367  1.0
  O  O34  1  0.212  0.933  0.571  1.0
  O  O35  1  0.788  0.933  0.071  1.0
[/CIF]
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