The structure described by CaFe4As3 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent As(1), two equivalent As(2), and three equivalent As(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(1), one As(2), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the second Fe site, Fe(2) is bonded to one As(1), one As(3), and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the third Fe site, Fe(3) is bonded in a 5-coordinate geometry to one As(3), two equivalent As(1), and two equivalent As(2) atoms. In the fourth Fe site, Fe(4) is bonded to one As(2) and three equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Fe(1), one Fe(2), two equivalent Fe(3), and three equivalent Fe(4) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Ca(1), one Fe(1), one Fe(4), two equivalent Fe(2), and two equivalent Fe(3) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to three equivalent Ca(1), one Fe(2), one Fe(3), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CaFe4As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.745
_cell_length_b   11.347
_cell_length_c   11.902
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   505.717
_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
  Ca  Ca0  1  0.250  0.067  0.833  1.0
  Ca  Ca1  1  0.750  0.933  0.167  1.0
  Ca  Ca2  1  0.750  0.567  0.667  1.0
  Ca  Ca3  1  0.250  0.433  0.333  1.0
  Fe  Fe4  1  0.250  0.775  0.811  1.0
  Fe  Fe5  1  0.750  0.225  0.189  1.0
  Fe  Fe6  1  0.750  0.275  0.689  1.0
  Fe  Fe7  1  0.250  0.725  0.311  1.0
  Fe  Fe8  1  0.250  0.371  0.807  1.0
  Fe  Fe9  1  0.750  0.629  0.193  1.0
  Fe  Fe10  1  0.750  0.871  0.693  1.0
  Fe  Fe11  1  0.250  0.129  0.307  1.0
  Fe  Fe12  1  0.250  0.317  0.014  1.0
  Fe  Fe13  1  0.750  0.683  0.986  1.0
  Fe  Fe14  1  0.750  0.817  0.486  1.0
  Fe  Fe15  1  0.250  0.183  0.514  1.0
  Fe  Fe16  1  0.250  0.539  0.068  1.0
  Fe  Fe17  1  0.750  0.461  0.932  1.0
  Fe  Fe18  1  0.750  0.039  0.432  1.0
  Fe  Fe19  1  0.250  0.961  0.568  1.0
  As  As20  1  0.250  0.575  0.873  1.0
  As  As21  1  0.750  0.425  0.127  1.0
  As  As22  1  0.750  0.075  0.627  1.0
  As  As23  1  0.250  0.925  0.373  1.0
  As  As24  1  0.250  0.760  0.612  1.0
  As  As25  1  0.750  0.240  0.388  1.0
  As  As26  1  0.750  0.260  0.888  1.0
  As  As27  1  0.250  0.740  0.112  1.0
  As  As28  1  0.250  0.373  0.603  1.0
  As  As29  1  0.750  0.627  0.397  1.0
  As  As30  1  0.750  0.873  0.897  1.0
  As  As31  1  0.250  0.127  0.103  1.0
[/CIF]
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The structure described by CaFe4As3 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 7-coordinate geometry to two equivalent As(1), two equivalent As(2), and three equivalent As(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one As(1), one As(2), and two equivalent As(3) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the second Fe site, Fe(2) is bonded to one As(1), one As(3), and two equivalent As(2) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. In the third Fe site, Fe(3) is bonded in a 5-coordinate geometry to one As(3), two equivalent As(1), and two equivalent As(2) atoms. In the fourth Fe site, Fe(4) is bonded to one As(2) and three equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing FeAs4 tetrahedra. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Fe(1), one Fe(2), two equivalent Fe(3), and three equivalent Fe(4) atoms. In the second As site, As(2) is bonded in a 8-coordinate geometry to two equivalent Ca(1), one Fe(1), one Fe(4), two equivalent Fe(2), and two equivalent Fe(3) atoms. In the third As site, As(3) is bonded in a 7-coordinate geometry to three equivalent Ca(1), one Fe(2), one Fe(3), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_CaFe4As3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.745
_cell_length_b   11.347
_cell_length_c   11.902
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   505.717
_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
  Ca  Ca0  1  0.250  0.067  0.833  1.0
  Ca  Ca1  1  0.750  0.933  0.167  1.0
  Ca  Ca2  1  0.750  0.567  0.667  1.0
  Ca  Ca3  1  0.250  0.433  0.333  1.0
  Fe  Fe4  1  0.250  0.775  0.811  1.0
  Fe  Fe5  1  0.750  0.225  0.189  1.0
  Fe  Fe6  1  0.750  0.275  0.689  1.0
  Fe  Fe7  1  0.250  0.725  0.311  1.0
  Fe  Fe8  1  0.250  0.371  0.807  1.0
  Fe  Fe9  1  0.750  0.629  0.193  1.0
  Fe  Fe10  1  0.750  0.871  0.693  1.0
  Fe  Fe11  1  0.250  0.129  0.307  1.0
  Fe  Fe12  1  0.250  0.317  0.014  1.0
  Fe  Fe13  1  0.750  0.683  0.986  1.0
  Fe  Fe14  1  0.750  0.817  0.486  1.0
  Fe  Fe15  1  0.250  0.183  0.514  1.0
  Fe  Fe16  1  0.250  0.539  0.068  1.0
  Fe  Fe17  1  0.750  0.461  0.932  1.0
  Fe  Fe18  1  0.750  0.039  0.432  1.0
  Fe  Fe19  1  0.250  0.961  0.568  1.0
  As  As20  1  0.250  0.575  0.873  1.0
  As  As21  1  0.750  0.425  0.127  1.0
  As  As22  1  0.750  0.075  0.627  1.0
  As  As23  1  0.250  0.925  0.373  1.0
  As  As24  1  0.250  0.760  0.612  1.0
  As  As25  1  0.750  0.240  0.388  1.0
  As  As26  1  0.750  0.260  0.888  1.0
  As  As27  1  0.250  0.740  0.112  1.0
  As  As28  1  0.250  0.373  0.603  1.0
  As  As29  1  0.750  0.627  0.397  1.0
  As  As30  1  0.750  0.873  0.897  1.0
  As  As31  1  0.250  0.127  0.103  1.0
[/CIF]
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