The material described by Li2CuAsO4 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 As(1)O4 tetrahedra. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(4) atoms. Cu(1) is bonded in a 2-coordinate geometry to one O(2), one O(3), and two equivalent O(4) atoms. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 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 As(1) atom to form distorted OLi3As tetrahedra that share corners with two equivalent O(1)Li3As tetrahedra, corners with two equivalent O(2)Li2CuAs trigonal pyramids, and  an edgeedge with one O(2)Li2CuAs trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Cu(1), and one As(1) atom to form a mixture of distorted corner and edge-sharing OLi2CuAs trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Cu(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Li(2), two equivalent Cu(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2CuAsO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.174
_cell_length_b   6.980
_cell_length_c   10.909
_cell_angle_alpha   88.531
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   393.834
_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  0.232  0.989  0.846  1.0
  Li  Li1  1  0.268  0.989  0.346  1.0
  Li  Li2  1  0.270  0.322  0.700  1.0
  Li  Li3  1  0.230  0.322  0.200  1.0
  Li  Li4  1  0.770  0.678  0.800  1.0
  Li  Li5  1  0.730  0.678  0.300  1.0
  Li  Li6  1  0.732  0.011  0.654  1.0
  Li  Li7  1  0.768  0.011  0.154  1.0
  Cu  Cu8  1  0.305  0.500  0.914  1.0
  Cu  Cu9  1  0.805  0.500  0.586  1.0
  Cu  Cu10  1  0.195  0.500  0.414  1.0
  Cu  Cu11  1  0.695  0.500  0.086  1.0
  As  As12  1  0.751  0.235  0.888  1.0
  As  As13  1  0.749  0.235  0.388  1.0
  As  As14  1  0.251  0.765  0.612  1.0
  As  As15  1  0.249  0.765  0.112  1.0
  O  O16  1  0.851  0.023  0.830  1.0
  O  O17  1  0.649  0.023  0.330  1.0
  O  O18  1  0.416  0.249  0.865  1.0
  O  O19  1  0.702  0.247  0.545  1.0
  O  O20  1  0.084  0.249  0.365  1.0
  O  O21  1  0.914  0.416  0.810  1.0
  O  O22  1  0.798  0.247  0.045  1.0
  O  O23  1  0.586  0.416  0.310  1.0
  O  O24  1  0.414  0.584  0.690  1.0
  O  O25  1  0.202  0.753  0.955  1.0
  O  O26  1  0.086  0.584  0.190  1.0
  O  O27  1  0.916  0.751  0.635  1.0
  O  O28  1  0.298  0.753  0.455  1.0
  O  O29  1  0.584  0.751  0.135  1.0
  O  O30  1  0.351  0.977  0.670  1.0
  O  O31  1  0.149  0.977  0.170  1.0
[/CIF]
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The material described by Li2CuAsO4 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 As(1)O4 tetrahedra. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(4) atoms. Cu(1) is bonded in a 2-coordinate geometry to one O(2), one O(3), and two equivalent O(4) atoms. As(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AsO4 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 As(1) atom to form distorted OLi3As tetrahedra that share corners with two equivalent O(1)Li3As tetrahedra, corners with two equivalent O(2)Li2CuAs trigonal pyramids, and  an edgeedge with one O(2)Li2CuAs trigonal pyramid. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Cu(1), and one As(1) atom to form a mixture of distorted corner and edge-sharing OLi2CuAs trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Cu(1), and one As(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Li(2), two equivalent Cu(1), and one As(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2CuAsO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.174
_cell_length_b   6.980
_cell_length_c   10.909
_cell_angle_alpha   88.531
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   393.834
_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  0.232  0.989  0.846  1.0
  Li  Li1  1  0.268  0.989  0.346  1.0
  Li  Li2  1  0.270  0.322  0.700  1.0
  Li  Li3  1  0.230  0.322  0.200  1.0
  Li  Li4  1  0.770  0.678  0.800  1.0
  Li  Li5  1  0.730  0.678  0.300  1.0
  Li  Li6  1  0.732  0.011  0.654  1.0
  Li  Li7  1  0.768  0.011  0.154  1.0
  Cu  Cu8  1  0.305  0.500  0.914  1.0
  Cu  Cu9  1  0.805  0.500  0.586  1.0
  Cu  Cu10  1  0.195  0.500  0.414  1.0
  Cu  Cu11  1  0.695  0.500  0.086  1.0
  As  As12  1  0.751  0.235  0.888  1.0
  As  As13  1  0.749  0.235  0.388  1.0
  As  As14  1  0.251  0.765  0.612  1.0
  As  As15  1  0.249  0.765  0.112  1.0
  O  O16  1  0.851  0.023  0.830  1.0
  O  O17  1  0.649  0.023  0.330  1.0
  O  O18  1  0.416  0.249  0.865  1.0
  O  O19  1  0.702  0.247  0.545  1.0
  O  O20  1  0.084  0.249  0.365  1.0
  O  O21  1  0.914  0.416  0.810  1.0
  O  O22  1  0.798  0.247  0.045  1.0
  O  O23  1  0.586  0.416  0.310  1.0
  O  O24  1  0.414  0.584  0.690  1.0
  O  O25  1  0.202  0.753  0.955  1.0
  O  O26  1  0.086  0.584  0.190  1.0
  O  O27  1  0.916  0.751  0.635  1.0
  O  O28  1  0.298  0.753  0.455  1.0
  O  O29  1  0.584  0.751  0.135  1.0
  O  O30  1  0.351  0.977  0.670  1.0
  O  O31  1  0.149  0.977  0.170  1.0
[/CIF]
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