The compound described by ErAsS is Matlockite structured and crystallizes in the orthorhombic Pmmn space group. Er(1) is bonded in a 9-coordinate geometry to four equivalent As(1) and five equivalent S(1) atoms. As(1) is bonded to four equivalent Er(1) and four equivalent As(1) atoms to form distorted AsEr4As4 hexagonal bipyramids that share corners with four equivalent As(1)Er4As4 hexagonal bipyramids, corners with twelve equivalent S(1)Er5 trigonal bipyramids, edges with four equivalent As(1)Er4As4 hexagonal bipyramids, edges with four equivalent S(1)Er5 trigonal bipyramids, and faces with four equivalent As(1)Er4As4 hexagonal bipyramids. S(1) is bonded to five equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with twelve equivalent As(1)Er4As4 hexagonal bipyramids, corners with four equivalent S(1)Er5 trigonal bipyramids, edges with four equivalent As(1)Er4As4 hexagonal bipyramids, and edges with eight equivalent S(1)Er5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErAsS
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.807
_cell_length_b   3.821
_cell_length_c   8.477
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   123.314
_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
  Er  Er0  1  0.250  0.250  0.709  1.0
  Er  Er1  1  0.750  0.750  0.291  1.0
  As  As2  1  0.750  0.250  0.003  1.0
  As  As3  1  0.250  0.750  0.997  1.0
  S  S4  1  0.250  0.250  0.375  1.0
  S  S5  1  0.750  0.750  0.625  1.0
[/CIF]
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The compound described by ErAsS is Matlockite structured and crystallizes in the orthorhombic Pmmn space group. Er(1) is bonded in a 9-coordinate geometry to four equivalent As(1) and five equivalent S(1) atoms. As(1) is bonded to four equivalent Er(1) and four equivalent As(1) atoms to form distorted AsEr4As4 hexagonal bipyramids that share corners with four equivalent As(1)Er4As4 hexagonal bipyramids, corners with twelve equivalent S(1)Er5 trigonal bipyramids, edges with four equivalent As(1)Er4As4 hexagonal bipyramids, edges with four equivalent S(1)Er5 trigonal bipyramids, and faces with four equivalent As(1)Er4As4 hexagonal bipyramids. S(1) is bonded to five equivalent Er(1) atoms to form distorted SEr5 trigonal bipyramids that share corners with twelve equivalent As(1)Er4As4 hexagonal bipyramids, corners with four equivalent S(1)Er5 trigonal bipyramids, edges with four equivalent As(1)Er4As4 hexagonal bipyramids, and edges with eight equivalent S(1)Er5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_ErAsS
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.807
_cell_length_b   3.821
_cell_length_c   8.477
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   123.314
_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
  Er  Er0  1  0.250  0.250  0.709  1.0
  Er  Er1  1  0.750  0.750  0.291  1.0
  As  As2  1  0.750  0.250  0.003  1.0
  As  As3  1  0.250  0.750  0.997  1.0
  S  S4  1  0.250  0.250  0.375  1.0
  S  S5  1  0.750  0.750  0.625  1.0
[/CIF]
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