The structure described by BaZn2Si2O7 crystallizes in the orthorhombic Cmcm space group. Ba(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. Zn(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with four equivalent Zn(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Zn(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ba(1), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1) and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaZn2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.668
_cell_length_b   7.668
_cell_length_c   6.712
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.127
_symmetry_Int_Tables_number   1
_cell_volume   351.212
_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
  Ba  Ba0  1  0.229  0.229  0.250  1.0
  Ba  Ba1  1  0.771  0.771  0.750  1.0
  Zn  Zn2  1  0.276  0.724  0.500  1.0
  Zn  Zn3  1  0.724  0.276  0.500  1.0
  Zn  Zn4  1  0.276  0.724  0.000  1.0
  Zn  Zn5  1  0.724  0.276  0.000  1.0
  Si  Si6  1  0.087  0.324  0.750  1.0
  Si  Si7  1  0.324  0.087  0.750  1.0
  Si  Si8  1  0.676  0.913  0.250  1.0
  Si  Si9  1  0.913  0.676  0.250  1.0
  O  O10  1  0.770  0.156  0.250  1.0
  O  O11  1  0.820  0.559  0.455  1.0
  O  O12  1  0.844  0.230  0.750  1.0
  O  O13  1  0.820  0.559  0.045  1.0
  O  O14  1  0.230  0.844  0.750  1.0
  O  O15  1  0.119  0.119  0.750  1.0
  O  O16  1  0.180  0.441  0.545  1.0
  O  O17  1  0.559  0.820  0.455  1.0
  O  O18  1  0.180  0.441  0.955  1.0
  O  O19  1  0.441  0.180  0.955  1.0
  O  O20  1  0.881  0.881  0.250  1.0
  O  O21  1  0.559  0.820  0.045  1.0
  O  O22  1  0.441  0.180  0.545  1.0
  O  O23  1  0.156  0.770  0.250  1.0
[/CIF]
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The structure described by BaZn2Si2O7 crystallizes in the orthorhombic Cmcm space group. Ba(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. Zn(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with two equivalent Zn(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with four equivalent Zn(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Zn(1) and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ba(1), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1) and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaZn2Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.668
_cell_length_b   7.668
_cell_length_c   6.712
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.127
_symmetry_Int_Tables_number   1
_cell_volume   351.212
_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
  Ba  Ba0  1  0.229  0.229  0.250  1.0
  Ba  Ba1  1  0.771  0.771  0.750  1.0
  Zn  Zn2  1  0.276  0.724  0.500  1.0
  Zn  Zn3  1  0.724  0.276  0.500  1.0
  Zn  Zn4  1  0.276  0.724  0.000  1.0
  Zn  Zn5  1  0.724  0.276  0.000  1.0
  Si  Si6  1  0.087  0.324  0.750  1.0
  Si  Si7  1  0.324  0.087  0.750  1.0
  Si  Si8  1  0.676  0.913  0.250  1.0
  Si  Si9  1  0.913  0.676  0.250  1.0
  O  O10  1  0.770  0.156  0.250  1.0
  O  O11  1  0.820  0.559  0.455  1.0
  O  O12  1  0.844  0.230  0.750  1.0
  O  O13  1  0.820  0.559  0.045  1.0
  O  O14  1  0.230  0.844  0.750  1.0
  O  O15  1  0.119  0.119  0.750  1.0
  O  O16  1  0.180  0.441  0.545  1.0
  O  O17  1  0.559  0.820  0.455  1.0
  O  O18  1  0.180  0.441  0.955  1.0
  O  O19  1  0.441  0.180  0.955  1.0
  O  O20  1  0.881  0.881  0.250  1.0
  O  O21  1  0.559  0.820  0.045  1.0
  O  O22  1  0.441  0.180  0.545  1.0
  O  O23  1  0.156  0.770  0.250  1.0
[/CIF]
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