data_BeSiP2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.39
_cell_length_b   3.39
_cell_length_c   4.82
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeSiP2
_chemical_formula_sum   'Be1 Si1 P2'
_cell_volume   55.54
_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
  Be  Be0  1  0.0  0.0  0.18  1.0
  Si  Si3  1  0.7  0.7  0.81  1.0
  P  P1  1  0.7  0.7  0.24  1.0
  P  P2  1  0.0  0.0  0.83  1.0

data_BeSiP2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.8
_cell_length_b   4.8
_cell_length_c   4.82
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   BeSiP2
_chemical_formula_sum   'Be2 Si2 P4'
_cell_volume   111.07
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Be  Be0  2  0.0  0.0  0.18  1.0
  Si  Si1  2  0.2  0.5  0.81  1.0
  P  P2  2  0.0  0.0  0.83  1.0
  P  P3  2  0.2  0.5  0.24  1.0

Be Si P P
Be Si P P 0 2 - - o 0 3 o o - 1 3 + + o 
BeSiP2 crystallizes in the monoclinic Cm space group. Be(1) is bonded in a distorted water-like geometry to one P(1) and one P(2) atom. The Be(1)-P(1) bond length is 1.48 Å. The Be(1)-P(2) bond length is 1.66 Å. Si(1) is bonded in a 5-coordinate geometry to two equivalent P(1) and three equivalent P(2) atoms. There is one shorter (2.06 Å) and one longer (2.76 Å) Si(1)-P(1) bond length. There is one shorter (1.46 Å) and two longer (2.58 Å) Si(1)-P(2) bond lengths. There are two inequivalent P sites. In the first P site, P(1) is bonded in a distorted single-bond geometry to one Be(1) and two equivalent Si(1) atoms. In the second P site, P(2) is bonded in a distorted L-shaped geometry to one Be(1) and three equivalent Si(1) atoms.