The structure described by Ca2Ni7P4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 17-coordinate geometry to one Ni(2), one Ni(4), one Ni(5), two equivalent Ni(6), three equivalent Ni(1), three equivalent Ni(3), two equivalent P(1), two equivalent P(2), and two equivalent P(3) atoms. In the second Ca site, Ca(2) is bonded in a 16-coordinate geometry to one Ni(3), one Ni(4), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), three equivalent Ni(7), two equivalent P(3), and three equivalent P(4) atoms. There are seven inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to three equivalent Ca(1), one P(1), one P(3), and two equivalent P(2) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(2), one P(3), one P(4), and two equivalent P(1) atoms. In the third Ni site, Ni(3) is bonded to one Ca(2), three equivalent Ca(1), one P(1), one P(2), and two equivalent P(3) atoms to form a mixture of distorted corner and edge-sharing NiCa4P4 tetrahedra. In the fourth Ni site, Ni(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ca(2), one P(2), and two equivalent P(1) atoms. In the fifth Ni site, Ni(5) is bonded in a 3-coordinate geometry to one Ca(1), two equivalent Ca(2), one P(4), and two equivalent P(2) atoms. In the sixth Ni site, Ni(6) is bonded in a 4-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one P(2), one P(3), and two equivalent P(4) atoms. In the seventh Ni site, Ni(7) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ca(2), one P(1), and two equivalent P(4) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Ni(1), one Ni(3), one Ni(7), two equivalent Ni(2), and two equivalent Ni(4) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Ni(3), one Ni(4), one Ni(6), two equivalent Ni(1), and two equivalent Ni(5) atoms. In the third P site, P(3) is bonded in a 9-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Ni(1), one Ni(2), one Ni(6), and two equivalent Ni(3) atoms. In the fourth P site, P(4) is bonded in a 9-coordinate geometry to three equivalent Ca(2), one Ni(2), one Ni(5), two equivalent Ni(6), and two equivalent Ni(7) atoms. is represented by the CIF file [CIF]
data_Ca2Ni7P4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.669
_cell_length_b   9.125
_cell_length_c   10.308
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   345.140
_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  0.000  0.061  0.394  1.0
  Ca  Ca1  1  0.500  0.939  0.894  1.0
  Ca  Ca2  1  0.000  0.438  0.179  1.0
  Ca  Ca3  1  0.500  0.562  0.679  1.0
  Ni  Ni4  1  0.000  0.061  0.701  1.0
  Ni  Ni5  1  0.500  0.939  0.201  1.0
  Ni  Ni6  1  0.000  0.729  0.507  1.0
  Ni  Ni7  1  0.500  0.271  0.007  1.0
  Ni  Ni8  1  0.000  0.094  0.095  1.0
  Ni  Ni9  1  0.500  0.906  0.595  1.0
  Ni  Ni10  1  0.000  0.747  0.274  1.0
  Ni  Ni11  1  0.500  0.253  0.774  1.0
  Ni  Ni12  1  0.000  0.304  0.600  1.0
  Ni  Ni13  1  0.500  0.696  0.100  1.0
  Ni  Ni14  1  0.000  0.684  0.915  1.0
  Ni  Ni15  1  0.500  0.316  0.415  1.0
  Ni  Ni16  1  0.000  0.416  0.874  1.0
  Ni  Ni17  1  0.500  0.584  0.374  1.0
  P  P18  1  0.000  0.181  0.892  1.0
  P  P19  1  0.500  0.819  0.392  1.0
  P  P20  1  0.000  0.842  0.084  1.0
  P  P21  1  0.500  0.158  0.584  1.0
  P  P22  1  0.000  0.814  0.710  1.0
  P  P23  1  0.500  0.186  0.210  1.0
  P  P24  1  0.000  0.478  0.459  1.0
  P  P25  1  0.500  0.522  0.959  1.0
[/CIF]
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The structure described by Ca2Ni7P4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 17-coordinate geometry to one Ni(2), one Ni(4), one Ni(5), two equivalent Ni(6), three equivalent Ni(1), three equivalent Ni(3), two equivalent P(1), two equivalent P(2), and two equivalent P(3) atoms. In the second Ca site, Ca(2) is bonded in a 16-coordinate geometry to one Ni(3), one Ni(4), two equivalent Ni(2), two equivalent Ni(5), two equivalent Ni(6), three equivalent Ni(7), two equivalent P(3), and three equivalent P(4) atoms. There are seven inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to three equivalent Ca(1), one P(1), one P(3), and two equivalent P(2) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ca(2), one P(3), one P(4), and two equivalent P(1) atoms. In the third Ni site, Ni(3) is bonded to one Ca(2), three equivalent Ca(1), one P(1), one P(2), and two equivalent P(3) atoms to form a mixture of distorted corner and edge-sharing NiCa4P4 tetrahedra. In the fourth Ni site, Ni(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ca(2), one P(2), and two equivalent P(1) atoms. In the fifth Ni site, Ni(5) is bonded in a 3-coordinate geometry to one Ca(1), two equivalent Ca(2), one P(4), and two equivalent P(2) atoms. In the sixth Ni site, Ni(6) is bonded in a 4-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one P(2), one P(3), and two equivalent P(4) atoms. In the seventh Ni site, Ni(7) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ca(2), one P(1), and two equivalent P(4) atoms. There are four inequivalent P sites. In the first P site, P(1) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Ni(1), one Ni(3), one Ni(7), two equivalent Ni(2), and two equivalent Ni(4) atoms. In the second P site, P(2) is bonded in a 9-coordinate geometry to two equivalent Ca(1), one Ni(3), one Ni(4), one Ni(6), two equivalent Ni(1), and two equivalent Ni(5) atoms. In the third P site, P(3) is bonded in a 9-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), one Ni(1), one Ni(2), one Ni(6), and two equivalent Ni(3) atoms. In the fourth P site, P(4) is bonded in a 9-coordinate geometry to three equivalent Ca(2), one Ni(2), one Ni(5), two equivalent Ni(6), and two equivalent Ni(7) atoms. is represented by the CIF file [CIF]
data_Ca2Ni7P4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.669
_cell_length_b   9.125
_cell_length_c   10.308
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   345.140
_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  0.000  0.061  0.394  1.0
  Ca  Ca1  1  0.500  0.939  0.894  1.0
  Ca  Ca2  1  0.000  0.438  0.179  1.0
  Ca  Ca3  1  0.500  0.562  0.679  1.0
  Ni  Ni4  1  0.000  0.061  0.701  1.0
  Ni  Ni5  1  0.500  0.939  0.201  1.0
  Ni  Ni6  1  0.000  0.729  0.507  1.0
  Ni  Ni7  1  0.500  0.271  0.007  1.0
  Ni  Ni8  1  0.000  0.094  0.095  1.0
  Ni  Ni9  1  0.500  0.906  0.595  1.0
  Ni  Ni10  1  0.000  0.747  0.274  1.0
  Ni  Ni11  1  0.500  0.253  0.774  1.0
  Ni  Ni12  1  0.000  0.304  0.600  1.0
  Ni  Ni13  1  0.500  0.696  0.100  1.0
  Ni  Ni14  1  0.000  0.684  0.915  1.0
  Ni  Ni15  1  0.500  0.316  0.415  1.0
  Ni  Ni16  1  0.000  0.416  0.874  1.0
  Ni  Ni17  1  0.500  0.584  0.374  1.0
  P  P18  1  0.000  0.181  0.892  1.0
  P  P19  1  0.500  0.819  0.392  1.0
  P  P20  1  0.000  0.842  0.084  1.0
  P  P21  1  0.500  0.158  0.584  1.0
  P  P22  1  0.000  0.814  0.710  1.0
  P  P23  1  0.500  0.186  0.210  1.0
  P  P24  1  0.000  0.478  0.459  1.0
  P  P25  1  0.500  0.522  0.959  1.0
[/CIF]
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