The crystal structure described by U3Pa is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Pa(1) atoms to form distorted UU8Pa4 cuboctahedra that share corners with twelve equivalent U(1)U8Pa4 cuboctahedra, edges with eight equivalent U(1)U8Pa4 cuboctahedra, edges with eight equivalent Pa(1)U12 cuboctahedra, faces with four equivalent Pa(1)U12 cuboctahedra, and faces with ten equivalent U(1)U8Pa4 cuboctahedra. In the second U site, U(2) is bonded in a square co-planar geometry to eight equivalent U(1) and four equivalent Pa(1) atoms. Pa(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form distorted PaU12 cuboctahedra that share corners with four equivalent Pa(1)U12 cuboctahedra, edges with eight equivalent Pa(1)U12 cuboctahedra, edges with sixteen equivalent U(1)U8Pa4 cuboctahedra, faces with four equivalent Pa(1)U12 cuboctahedra, and faces with eight equivalent U(1)U8Pa4 cuboctahedra. is represented by the CIF card [CIF]
data_U3Pa
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.993
_cell_length_b   5.993
_cell_length_c   5.993
_cell_angle_alpha   140.733
_cell_angle_beta   140.733
_cell_angle_gamma   56.741
_symmetry_Int_Tables_number   1
_cell_volume   85.537
_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
  U  U0  1  0.750  0.250  0.500  1.0
  U  U1  1  0.250  0.750  0.500  1.0
  U  U2  1  0.500  0.500  0.000  1.0
  Pa  Pa3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by U3Pa is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to four equivalent U(1), four equivalent U(2), and four equivalent Pa(1) atoms to form distorted UU8Pa4 cuboctahedra that share corners with twelve equivalent U(1)U8Pa4 cuboctahedra, edges with eight equivalent U(1)U8Pa4 cuboctahedra, edges with eight equivalent Pa(1)U12 cuboctahedra, faces with four equivalent Pa(1)U12 cuboctahedra, and faces with ten equivalent U(1)U8Pa4 cuboctahedra. In the second U site, U(2) is bonded in a square co-planar geometry to eight equivalent U(1) and four equivalent Pa(1) atoms. Pa(1) is bonded to four equivalent U(2) and eight equivalent U(1) atoms to form distorted PaU12 cuboctahedra that share corners with four equivalent Pa(1)U12 cuboctahedra, edges with eight equivalent Pa(1)U12 cuboctahedra, edges with sixteen equivalent U(1)U8Pa4 cuboctahedra, faces with four equivalent Pa(1)U12 cuboctahedra, and faces with eight equivalent U(1)U8Pa4 cuboctahedra. is represented by the CIF card [CIF]
data_U3Pa
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.993
_cell_length_b   5.993
_cell_length_c   5.993
_cell_angle_alpha   140.733
_cell_angle_beta   140.733
_cell_angle_gamma   56.741
_symmetry_Int_Tables_number   1
_cell_volume   85.537
_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
  U  U0  1  0.750  0.250  0.500  1.0
  U  U1  1  0.250  0.750  0.500  1.0
  U  U2  1  0.500  0.500  0.000  1.0
  Pa  Pa3  1  0.000  0.000  0.000  1.0
[/CIF]
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