The structure described by Li3CrB4O9 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(3), one O(4), and one O(6) atom. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(2), one O(5), two equivalent O(4), and two equivalent O(6) atoms. Cr(1) is bonded to one O(3), one O(5), and two equivalent O(6) atoms to form CrO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and  a cornercorner with one B(2)O4 tetrahedra. There are three inequivalent B sites. In the first B site, B(1) is bonded to one O(2), one O(5), and two equivalent O(1) atoms to form BO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra and  a cornercorner with one B(2)O4 tetrahedra. In the second B site, B(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form BO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra and  a cornercorner with one B(1)O4 tetrahedra. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(4), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one B(1), and one B(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(2), one B(1), and one B(2) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Cr(1), and one B(2) atom to form corner-sharing OLi2CrB tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one B(2), and one B(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Li(2), one Cr(1), and one B(1) atom. In the sixth O site, O(6) is bonded to one Li(1), one Li(2), one Cr(1), and one B(3) atom to form a mixture of distorted edge and corner-sharing OLi2CrB tetrahedra. is represented by the CIF file [CIF]
data_Li3CrB4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.544
_cell_length_b   5.893
_cell_length_c   6.704
_cell_angle_alpha   76.618
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   328.375
_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  0.436  0.762  0.160  1.0
  Li  Li1  1  0.064  0.762  0.160  1.0
  Li  Li2  1  0.750  0.586  0.502  1.0
  Li  Li3  1  0.250  0.414  0.498  1.0
  Li  Li4  1  0.936  0.238  0.840  1.0
  Li  Li5  1  0.564  0.238  0.840  1.0
  Cr  Cr6  1  0.750  0.752  0.887  1.0
  Cr  Cr7  1  0.250  0.248  0.113  1.0
  B  B8  1  0.750  0.998  0.231  1.0
  B  B9  1  0.250  0.864  0.459  1.0
  B  B10  1  0.457  0.717  0.717  1.0
  B  B11  1  0.043  0.717  0.717  1.0
  B  B12  1  0.957  0.283  0.283  1.0
  B  B13  1  0.543  0.283  0.283  1.0
  B  B14  1  0.750  0.136  0.541  1.0
  B  B15  1  0.250  0.002  0.769  1.0
  O  O16  1  0.396  0.854  0.843  1.0
  O  O17  1  0.104  0.854  0.843  1.0
  O  O18  1  0.750  0.933  0.454  1.0
  O  O19  1  0.250  0.920  0.236  1.0
  O  O20  1  0.389  0.710  0.532  1.0
  O  O21  1  0.111  0.710  0.532  1.0
  O  O22  1  0.750  0.788  0.155  1.0
  O  O23  1  0.911  0.583  0.778  1.0
  O  O24  1  0.589  0.583  0.778  1.0
  O  O25  1  0.089  0.417  0.222  1.0
  O  O26  1  0.411  0.417  0.222  1.0
  O  O27  1  0.250  0.212  0.845  1.0
  O  O28  1  0.889  0.290  0.468  1.0
  O  O29  1  0.611  0.290  0.468  1.0
  O  O30  1  0.750  0.080  0.764  1.0
  O  O31  1  0.250  0.067  0.546  1.0
  O  O32  1  0.896  0.146  0.157  1.0
  O  O33  1  0.604  0.146  0.157  1.0
[/CIF]
.
The structure described by Li3CrB4O9 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(3), one O(4), and one O(6) atom. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(2), one O(5), two equivalent O(4), and two equivalent O(6) atoms. Cr(1) is bonded to one O(3), one O(5), and two equivalent O(6) atoms to form CrO4 tetrahedra that share  a cornercorner with one B(1)O4 tetrahedra and  a cornercorner with one B(2)O4 tetrahedra. There are three inequivalent B sites. In the first B site, B(1) is bonded to one O(2), one O(5), and two equivalent O(1) atoms to form BO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra and  a cornercorner with one B(2)O4 tetrahedra. In the second B site, B(2) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form BO4 tetrahedra that share  a cornercorner with one Cr(1)O4 tetrahedra and  a cornercorner with one B(1)O4 tetrahedra. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(4), and one O(6) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(1), one B(1), and one B(3) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Li(2), one B(1), and one B(2) atom. In the third O site, O(3) is bonded to two equivalent Li(1), one Cr(1), and one B(2) atom to form corner-sharing OLi2CrB tetrahedra. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Li(1), one Li(2), one B(2), and one B(3) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Li(2), one Cr(1), and one B(1) atom. In the sixth O site, O(6) is bonded to one Li(1), one Li(2), one Cr(1), and one B(3) atom to form a mixture of distorted edge and corner-sharing OLi2CrB tetrahedra. is represented by the CIF file [CIF]
data_Li3CrB4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.544
_cell_length_b   5.893
_cell_length_c   6.704
_cell_angle_alpha   76.618
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   328.375
_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  0.436  0.762  0.160  1.0
  Li  Li1  1  0.064  0.762  0.160  1.0
  Li  Li2  1  0.750  0.586  0.502  1.0
  Li  Li3  1  0.250  0.414  0.498  1.0
  Li  Li4  1  0.936  0.238  0.840  1.0
  Li  Li5  1  0.564  0.238  0.840  1.0
  Cr  Cr6  1  0.750  0.752  0.887  1.0
  Cr  Cr7  1  0.250  0.248  0.113  1.0
  B  B8  1  0.750  0.998  0.231  1.0
  B  B9  1  0.250  0.864  0.459  1.0
  B  B10  1  0.457  0.717  0.717  1.0
  B  B11  1  0.043  0.717  0.717  1.0
  B  B12  1  0.957  0.283  0.283  1.0
  B  B13  1  0.543  0.283  0.283  1.0
  B  B14  1  0.750  0.136  0.541  1.0
  B  B15  1  0.250  0.002  0.769  1.0
  O  O16  1  0.396  0.854  0.843  1.0
  O  O17  1  0.104  0.854  0.843  1.0
  O  O18  1  0.750  0.933  0.454  1.0
  O  O19  1  0.250  0.920  0.236  1.0
  O  O20  1  0.389  0.710  0.532  1.0
  O  O21  1  0.111  0.710  0.532  1.0
  O  O22  1  0.750  0.788  0.155  1.0
  O  O23  1  0.911  0.583  0.778  1.0
  O  O24  1  0.589  0.583  0.778  1.0
  O  O25  1  0.089  0.417  0.222  1.0
  O  O26  1  0.411  0.417  0.222  1.0
  O  O27  1  0.250  0.212  0.845  1.0
  O  O28  1  0.889  0.290  0.468  1.0
  O  O29  1  0.611  0.290  0.468  1.0
  O  O30  1  0.750  0.080  0.764  1.0
  O  O31  1  0.250  0.067  0.546  1.0
  O  O32  1  0.896  0.146  0.157  1.0
  O  O33  1  0.604  0.146  0.157  1.0
[/CIF]
.