The compound described by Ca3Mo2O7 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) atoms. Mo(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing MoO6 octahedra. The corner-sharing octahedral tilt angles range from 28-30°. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(2) and one Mo(1) atom to form distorted OCa3Mo tetrahedra that share  a cornercorner with one O(4)Ca2Mo2 tetrahedra, corners with six equivalent O(1)Ca3Mo tetrahedra,  a cornercorner with one O(3)Ca3Mo2 trigonal bipyramid, and edges with two equivalent O(3)Ca3Mo2 trigonal bipyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), and two equivalent Mo(1) atoms. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Mo(1) atoms to form distorted OCa3Mo2 trigonal bipyramids that share  a cornercorner with one O(1)Ca3Mo tetrahedra, corners with four equivalent O(4)Ca2Mo2 tetrahedra, corners with two equivalent O(3)Ca3Mo2 trigonal bipyramids,  an edgeedge with one O(4)Ca2Mo2 tetrahedra, edges with two equivalent O(1)Ca3Mo tetrahedra, and edges with three equivalent O(3)Ca3Mo2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and two equivalent Mo(1) atoms to form distorted OCa2Mo2 tetrahedra that share corners with two equivalent O(4)Ca2Mo2 tetrahedra, corners with two equivalent O(1)Ca3Mo tetrahedra, corners with eight equivalent O(3)Ca3Mo2 trigonal bipyramids, and edges with two equivalent O(3)Ca3Mo2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3Mo2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.238
_cell_length_b   10.238
_cell_length_c   5.602
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.920
_symmetry_Int_Tables_number   1
_cell_volume   303.096
_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
  Ca  Ca0  1  0.242  0.242  0.299  1.0
  Ca  Ca1  1  0.758  0.758  0.799  1.0
  Ca  Ca2  1  0.049  0.429  0.202  1.0
  Ca  Ca3  1  0.951  0.571  0.702  1.0
  Ca  Ca4  1  0.429  0.049  0.202  1.0
  Ca  Ca5  1  0.571  0.951  0.702  1.0
  Mo  Mo6  1  0.848  0.648  0.250  1.0
  Mo  Mo7  1  0.152  0.352  0.750  1.0
  Mo  Mo8  1  0.352  0.152  0.750  1.0
  Mo  Mo9  1  0.648  0.848  0.250  1.0
  O  O10  1  0.626  0.026  0.280  1.0
  O  O11  1  0.374  0.974  0.780  1.0
  O  O12  1  0.974  0.374  0.780  1.0
  O  O13  1  0.026  0.626  0.280  1.0
  O  O14  1  0.429  0.663  0.955  1.0
  O  O15  1  0.571  0.337  0.455  1.0
  O  O16  1  0.337  0.571  0.455  1.0
  O  O17  1  0.663  0.429  0.955  1.0
  O  O18  1  0.965  0.128  0.047  1.0
  O  O19  1  0.035  0.872  0.547  1.0
  O  O20  1  0.658  0.658  0.214  1.0
  O  O21  1  0.342  0.342  0.714  1.0
  O  O22  1  0.128  0.965  0.047  1.0
  O  O23  1  0.872  0.035  0.547  1.0
[/CIF]
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The compound described by Ca3Mo2O7 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(2), and three equivalent O(1) atoms. Mo(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing MoO6 octahedra. The corner-sharing octahedral tilt angles range from 28-30°. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ca(2) and one Mo(1) atom to form distorted OCa3Mo tetrahedra that share  a cornercorner with one O(4)Ca2Mo2 tetrahedra, corners with six equivalent O(1)Ca3Mo tetrahedra,  a cornercorner with one O(3)Ca3Mo2 trigonal bipyramid, and edges with two equivalent O(3)Ca3Mo2 trigonal bipyramids. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Ca(1), two equivalent Ca(2), and two equivalent Mo(1) atoms. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Mo(1) atoms to form distorted OCa3Mo2 trigonal bipyramids that share  a cornercorner with one O(1)Ca3Mo tetrahedra, corners with four equivalent O(4)Ca2Mo2 tetrahedra, corners with two equivalent O(3)Ca3Mo2 trigonal bipyramids,  an edgeedge with one O(4)Ca2Mo2 tetrahedra, edges with two equivalent O(1)Ca3Mo tetrahedra, and edges with three equivalent O(3)Ca3Mo2 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Ca(1) and two equivalent Mo(1) atoms to form distorted OCa2Mo2 tetrahedra that share corners with two equivalent O(4)Ca2Mo2 tetrahedra, corners with two equivalent O(1)Ca3Mo tetrahedra, corners with eight equivalent O(3)Ca3Mo2 trigonal bipyramids, and edges with two equivalent O(3)Ca3Mo2 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca3Mo2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.238
_cell_length_b   10.238
_cell_length_c   5.602
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.920
_symmetry_Int_Tables_number   1
_cell_volume   303.096
_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
  Ca  Ca0  1  0.242  0.242  0.299  1.0
  Ca  Ca1  1  0.758  0.758  0.799  1.0
  Ca  Ca2  1  0.049  0.429  0.202  1.0
  Ca  Ca3  1  0.951  0.571  0.702  1.0
  Ca  Ca4  1  0.429  0.049  0.202  1.0
  Ca  Ca5  1  0.571  0.951  0.702  1.0
  Mo  Mo6  1  0.848  0.648  0.250  1.0
  Mo  Mo7  1  0.152  0.352  0.750  1.0
  Mo  Mo8  1  0.352  0.152  0.750  1.0
  Mo  Mo9  1  0.648  0.848  0.250  1.0
  O  O10  1  0.626  0.026  0.280  1.0
  O  O11  1  0.374  0.974  0.780  1.0
  O  O12  1  0.974  0.374  0.780  1.0
  O  O13  1  0.026  0.626  0.280  1.0
  O  O14  1  0.429  0.663  0.955  1.0
  O  O15  1  0.571  0.337  0.455  1.0
  O  O16  1  0.337  0.571  0.455  1.0
  O  O17  1  0.663  0.429  0.955  1.0
  O  O18  1  0.965  0.128  0.047  1.0
  O  O19  1  0.035  0.872  0.547  1.0
  O  O20  1  0.658  0.658  0.214  1.0
  O  O21  1  0.342  0.342  0.714  1.0
  O  O22  1  0.128  0.965  0.047  1.0
  O  O23  1  0.872  0.035  0.547  1.0
[/CIF]
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