data_ErTm2Be
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   5.17
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ErTm2Be
_chemical_formula_sum   'Er1 Tm2 Be1'
_cell_volume   97.93
_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
  Er  Er1  1  0.66  0.66  0.66  1.0
  Tm  Tm2  1  0.49  0.49  0.49  1.0
  Tm  Tm3  1  0.83  0.83  0.83  1.0
  Be  Be0  1  0.0  0.0  0.0  1.0

data_ErTm2Be
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   12.67
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ErTm2Be
_chemical_formula_sum   'Er3 Tm6 Be3'
_cell_volume   293.8
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  3  0.0  0.0  0.34  1.0
  Tm  Tm1  3  0.0  0.0  0.17  1.0
  Tm  Tm2  3  0.0  0.0  0.51  1.0
  Be  Be3  3  0.0  0.0  0.0  1.0

Er Tm Tm Be
Er Tm Tm Be 0 1 o o o 0 2 o o o 2 3 + + + 
BeTm2Er crystallizes in the trigonal R3m space group. Be(1) is bonded to one Tm(2) and three equivalent Er(1) atoms to form distorted BeEr3Tm trigonal pyramids that share  a cornercorner with one Er(1)Tm2Be3 trigonal bipyramid and corners with six equivalent Be(1)Er3Tm trigonal pyramids. The Be(1)-Tm(2) bond length is 2.16 Å. All Be(1)-Er(1) bond lengths are 2.99 Å. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a distorted single-bond geometry to one Er(1) atom. The Tm(1)-Er(1) bond length is 2.16 Å. In the second Tm site, Tm(2) is bonded in a distorted linear geometry to one Be(1) and one Er(1) atom. The Tm(2)-Er(1) bond length is 2.16 Å. Er(1) is bonded to three equivalent Be(1), one Tm(1), and one Tm(2) atom to form ErTm2Be3 trigonal bipyramids that share corners with six equivalent Er(1)Tm2Be3 trigonal bipyramids and  a cornercorner with one Be(1)Er3Tm trigonal pyramid.