The crystal structure described by Li2Cr3P9O28 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(7) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(13), two equivalent O(7), and two equivalent O(9) atoms to form CrO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are five inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(11), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(5)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-57°. In the second P site, P(2) is bonded to one O(12), one O(2), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the third P site, P(3) is bonded to one O(11), one O(14), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(5)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-53°. In the fourth P site, P(4) is bonded to one O(12), one O(13), one O(3), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(5)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-58°. In the fifth P site, P(5) is bonded to two equivalent O(10), two equivalent O(14), and two equivalent O(8) atoms to form corner-sharing PO6 octahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Cr(2), and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Cr(2), and one P(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one P(4) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cr(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one P(4) and one P(5) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one P(1) and one P(5) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one P(4) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one P(3) and one P(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr3P9O28
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.071
_cell_length_b   9.043
_cell_length_c   9.230
_cell_angle_alpha   111.646
_cell_angle_beta   109.836
_cell_angle_gamma   99.276
_symmetry_Int_Tables_number   1
_cell_volume   487.601
_cell_formula_units_Z   1
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  0.705  0.957  0.222  1.0
  Li  Li1  1  0.295  0.043  0.778  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Cr  Cr3  1  0.243  0.987  0.243  1.0
  Cr  Cr4  1  0.757  0.013  0.757  1.0
  P  P5  1  0.307  0.754  0.447  1.0
  P  P6  1  0.790  0.761  0.931  1.0
  P  P7  1  0.687  0.700  0.418  1.0
  P  P8  1  0.156  0.679  0.895  1.0
  P  P9  1  0.000  0.500  0.500  1.0
  P  P10  1  0.313  0.300  0.582  1.0
  P  P11  1  0.844  0.321  0.105  1.0
  P  P12  1  0.693  0.246  0.553  1.0
  P  P13  1  0.210  0.239  0.069  1.0
  O  O14  1  0.423  0.910  0.624  1.0
  O  O15  1  0.922  0.908  0.115  1.0
  O  O16  1  0.287  0.863  0.027  1.0
  O  O17  1  0.812  0.881  0.555  1.0
  O  O18  1  0.735  0.813  0.789  1.0
  O  O19  1  0.229  0.791  0.296  1.0
  O  O20  1  0.643  0.694  0.242  1.0
  O  O21  1  0.119  0.664  0.709  1.0
  O  O22  1  0.589  0.659  0.920  1.0
  O  O23  1  0.112  0.632  0.436  1.0
  O  O24  1  0.461  0.643  0.424  1.0
  O  O25  1  0.926  0.638  0.893  1.0
  O  O26  1  0.231  0.546  0.934  1.0
  O  O27  1  0.779  0.564  0.454  1.0
  O  O28  1  0.769  0.454  0.066  1.0
  O  O29  1  0.221  0.436  0.546  1.0
  O  O30  1  0.539  0.357  0.576  1.0
  O  O31  1  0.074  0.362  0.107  1.0
  O  O32  1  0.411  0.341  0.080  1.0
  O  O33  1  0.888  0.368  0.564  1.0
  O  O34  1  0.357  0.306  0.758  1.0
  O  O35  1  0.881  0.336  0.291  1.0
  O  O36  1  0.265  0.187  0.211  1.0
  O  O37  1  0.771  0.209  0.704  1.0
  O  O38  1  0.713  0.137  0.973  1.0
  O  O39  1  0.188  0.119  0.445  1.0
  O  O40  1  0.577  0.090  0.376  1.0
  O  O41  1  0.078  0.092  0.885  1.0
[/CIF]
.
The crystal structure described by Li2Cr3P9O28 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(7) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(13), two equivalent O(7), and two equivalent O(9) atoms to form CrO6 octahedra that share corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are five inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(10), one O(11), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(5)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-57°. In the second P site, P(2) is bonded to one O(12), one O(2), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Cr(2)O6 octahedra, and  a cornercorner with one P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-55°. In the third P site, P(3) is bonded to one O(11), one O(14), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(5)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 34-53°. In the fourth P site, P(4) is bonded to one O(12), one O(13), one O(3), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra,  a cornercorner with one Cr(2)O6 octahedra,  a cornercorner with one P(5)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-58°. In the fifth P site, P(5) is bonded to two equivalent O(10), two equivalent O(14), and two equivalent O(8) atoms to form corner-sharing PO6 octahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Cr(2), and one P(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Cr(2), and one P(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cr(2) and one P(4) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Cr(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Cr(2) and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(1), one Cr(1), and one P(3) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one P(4) and one P(5) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one P(1) and one P(5) atom. In the eleventh O site, O(11) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the twelfth O site, O(12) is bonded in a bent 120 degrees geometry to one P(2) and one P(4) atom. In the thirteenth O site, O(13) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one P(4) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one P(3) and one P(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Cr3P9O28
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.071
_cell_length_b   9.043
_cell_length_c   9.230
_cell_angle_alpha   111.646
_cell_angle_beta   109.836
_cell_angle_gamma   99.276
_symmetry_Int_Tables_number   1
_cell_volume   487.601
_cell_formula_units_Z   1
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  0.705  0.957  0.222  1.0
  Li  Li1  1  0.295  0.043  0.778  1.0
  Cr  Cr2  1  0.500  0.500  0.000  1.0
  Cr  Cr3  1  0.243  0.987  0.243  1.0
  Cr  Cr4  1  0.757  0.013  0.757  1.0
  P  P5  1  0.307  0.754  0.447  1.0
  P  P6  1  0.790  0.761  0.931  1.0
  P  P7  1  0.687  0.700  0.418  1.0
  P  P8  1  0.156  0.679  0.895  1.0
  P  P9  1  0.000  0.500  0.500  1.0
  P  P10  1  0.313  0.300  0.582  1.0
  P  P11  1  0.844  0.321  0.105  1.0
  P  P12  1  0.693  0.246  0.553  1.0
  P  P13  1  0.210  0.239  0.069  1.0
  O  O14  1  0.423  0.910  0.624  1.0
  O  O15  1  0.922  0.908  0.115  1.0
  O  O16  1  0.287  0.863  0.027  1.0
  O  O17  1  0.812  0.881  0.555  1.0
  O  O18  1  0.735  0.813  0.789  1.0
  O  O19  1  0.229  0.791  0.296  1.0
  O  O20  1  0.643  0.694  0.242  1.0
  O  O21  1  0.119  0.664  0.709  1.0
  O  O22  1  0.589  0.659  0.920  1.0
  O  O23  1  0.112  0.632  0.436  1.0
  O  O24  1  0.461  0.643  0.424  1.0
  O  O25  1  0.926  0.638  0.893  1.0
  O  O26  1  0.231  0.546  0.934  1.0
  O  O27  1  0.779  0.564  0.454  1.0
  O  O28  1  0.769  0.454  0.066  1.0
  O  O29  1  0.221  0.436  0.546  1.0
  O  O30  1  0.539  0.357  0.576  1.0
  O  O31  1  0.074  0.362  0.107  1.0
  O  O32  1  0.411  0.341  0.080  1.0
  O  O33  1  0.888  0.368  0.564  1.0
  O  O34  1  0.357  0.306  0.758  1.0
  O  O35  1  0.881  0.336  0.291  1.0
  O  O36  1  0.265  0.187  0.211  1.0
  O  O37  1  0.771  0.209  0.704  1.0
  O  O38  1  0.713  0.137  0.973  1.0
  O  O39  1  0.188  0.119  0.445  1.0
  O  O40  1  0.577  0.090  0.376  1.0
  O  O41  1  0.078  0.092  0.885  1.0
[/CIF]
.