The structure described by Li2CuSiO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. In the second Li site, Li(2) is bonded in a see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(4) atoms. 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 corners with four equivalent Li(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), and one Si(1) atom to form distorted OLi3Si tetrahedra that share corners with two equivalent O(2)Li2CuSi tetrahedra, corners with two equivalent O(1)Li3Si tetrahedra, corners with two equivalent O(3)Li2CuSi trigonal pyramids,  an edgeedge with one O(2)Li2CuSi tetrahedra, and  an edgeedge with one O(3)Li2CuSi trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Cu(1), and one Si(1) atom to form distorted OLi2CuSi tetrahedra that share corners with two equivalent O(1)Li3Si tetrahedra, corners with four equivalent O(3)Li2CuSi trigonal pyramids, and  an edgeedge with one O(1)Li3Si tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Cu(1), and one Si(1) atom to form distorted OLi2CuSi trigonal pyramids that share corners with two equivalent O(1)Li3Si tetrahedra, corners with four equivalent O(2)Li2CuSi tetrahedra, and  an edgeedge with one O(1)Li3Si tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(2), two equivalent Cu(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Li2CuSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   6.895
_cell_length_c   10.095
_cell_angle_alpha   89.813
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   358.244
_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
  Li  Li0  1  0.244  0.004  0.844  1.0
  Li  Li1  1  0.256  0.004  0.344  1.0
  Li  Li2  1  0.379  0.239  0.658  1.0
  Li  Li3  1  0.121  0.239  0.158  1.0
  Li  Li4  1  0.879  0.761  0.842  1.0
  Li  Li5  1  0.621  0.761  0.342  1.0
  Li  Li6  1  0.744  0.996  0.656  1.0
  Li  Li7  1  0.756  0.996  0.156  1.0
  Cu  Cu8  1  0.274  0.499  0.866  1.0
  Cu  Cu9  1  0.774  0.501  0.634  1.0
  Cu  Cu10  1  0.226  0.499  0.366  1.0
  Cu  Cu11  1  0.726  0.501  0.134  1.0
  Si  Si12  1  0.749  0.241  0.898  1.0
  Si  Si13  1  0.751  0.241  0.398  1.0
  Si  Si14  1  0.249  0.759  0.602  1.0
  Si  Si15  1  0.251  0.759  0.102  1.0
  O  O16  1  0.862  0.041  0.839  1.0
  O  O17  1  0.638  0.041  0.339  1.0
  O  O18  1  0.434  0.252  0.860  1.0
  O  O19  1  0.712  0.251  0.561  1.0
  O  O20  1  0.066  0.252  0.360  1.0
  O  O21  1  0.889  0.440  0.833  1.0
  O  O22  1  0.788  0.251  0.061  1.0
  O  O23  1  0.611  0.440  0.333  1.0
  O  O24  1  0.389  0.560  0.667  1.0
  O  O25  1  0.212  0.749  0.939  1.0
  O  O26  1  0.111  0.560  0.167  1.0
  O  O27  1  0.934  0.748  0.640  1.0
  O  O28  1  0.288  0.749  0.439  1.0
  O  O29  1  0.566  0.748  0.140  1.0
  O  O30  1  0.362  0.959  0.661  1.0
  O  O31  1  0.138  0.959  0.161  1.0
[/CIF]
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The structure described by Li2CuSiO4 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. In the second Li site, Li(2) is bonded in a see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. Cu(1) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(3), and two equivalent O(4) atoms. 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 corners with four equivalent Li(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(2), two equivalent Li(1), and one Si(1) atom to form distorted OLi3Si tetrahedra that share corners with two equivalent O(2)Li2CuSi tetrahedra, corners with two equivalent O(1)Li3Si tetrahedra, corners with two equivalent O(3)Li2CuSi trigonal pyramids,  an edgeedge with one O(2)Li2CuSi tetrahedra, and  an edgeedge with one O(3)Li2CuSi trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Cu(1), and one Si(1) atom to form distorted OLi2CuSi tetrahedra that share corners with two equivalent O(1)Li3Si tetrahedra, corners with four equivalent O(3)Li2CuSi trigonal pyramids, and  an edgeedge with one O(1)Li3Si tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Cu(1), and one Si(1) atom to form distorted OLi2CuSi trigonal pyramids that share corners with two equivalent O(1)Li3Si tetrahedra, corners with four equivalent O(2)Li2CuSi tetrahedra, and  an edgeedge with one O(1)Li3Si tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(2), two equivalent Cu(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Li2CuSiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   6.895
_cell_length_c   10.095
_cell_angle_alpha   89.813
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   358.244
_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
  Li  Li0  1  0.244  0.004  0.844  1.0
  Li  Li1  1  0.256  0.004  0.344  1.0
  Li  Li2  1  0.379  0.239  0.658  1.0
  Li  Li3  1  0.121  0.239  0.158  1.0
  Li  Li4  1  0.879  0.761  0.842  1.0
  Li  Li5  1  0.621  0.761  0.342  1.0
  Li  Li6  1  0.744  0.996  0.656  1.0
  Li  Li7  1  0.756  0.996  0.156  1.0
  Cu  Cu8  1  0.274  0.499  0.866  1.0
  Cu  Cu9  1  0.774  0.501  0.634  1.0
  Cu  Cu10  1  0.226  0.499  0.366  1.0
  Cu  Cu11  1  0.726  0.501  0.134  1.0
  Si  Si12  1  0.749  0.241  0.898  1.0
  Si  Si13  1  0.751  0.241  0.398  1.0
  Si  Si14  1  0.249  0.759  0.602  1.0
  Si  Si15  1  0.251  0.759  0.102  1.0
  O  O16  1  0.862  0.041  0.839  1.0
  O  O17  1  0.638  0.041  0.339  1.0
  O  O18  1  0.434  0.252  0.860  1.0
  O  O19  1  0.712  0.251  0.561  1.0
  O  O20  1  0.066  0.252  0.360  1.0
  O  O21  1  0.889  0.440  0.833  1.0
  O  O22  1  0.788  0.251  0.061  1.0
  O  O23  1  0.611  0.440  0.333  1.0
  O  O24  1  0.389  0.560  0.667  1.0
  O  O25  1  0.212  0.749  0.939  1.0
  O  O26  1  0.111  0.560  0.167  1.0
  O  O27  1  0.934  0.748  0.640  1.0
  O  O28  1  0.288  0.749  0.439  1.0
  O  O29  1  0.566  0.748  0.140  1.0
  O  O30  1  0.362  0.959  0.661  1.0
  O  O31  1  0.138  0.959  0.161  1.0
[/CIF]
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