data_KMgSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.88
_cell_length_b   4.88
_cell_length_c   6.99
_cell_angle_alpha   98.19
_cell_angle_beta   98.19
_cell_angle_gamma   37.22
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KMgSi2
_chemical_formula_sum   'K1 Mg1 Si2'
_cell_volume   99.61
_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
  K  K0  1  0.1  0.0  0.46  1.0
  Mg  Mg1  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.5  0.0  0.92  1.0
  Si  Si3  1  0.7  0.0  1.0  1.0

data_KMgSi2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.11
_cell_length_b   4.88
_cell_length_c   6.99
_cell_angle_alpha   98.19
_cell_angle_beta   90.0
_cell_angle_gamma   108.61
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KMgSi2
_chemical_formula_sum   'K1 Mg1 Si2'
_cell_volume   99.61
_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
  K  K0  1  0.0  0.9  0.54  1.0
  Mg  Mg1  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.0  0.3  0.0  1.0
  Si  Si3  1  0.0  0.5  0.08  1.0

K Mg Si Si
KMgSi2 crystallizes in the triclinic P1 space group. K(1) is bonded in a distorted hexagonal planar geometry to two equivalent K(1), two equivalent Mg(1), one Si(1), and one Si(2) atom. Both K(1)-K(1) bond lengths are 3.11 Å. There is one shorter (3.17 Å) and one longer (3.89 Å) K(1)-Mg(1) bond length. The K(1)-Si(1) bond length is 3.50 Å. The K(1)-Si(2) bond length is 3.50 Å. Mg(1) is bonded in a distorted single-bond geometry to two equivalent K(1), one Si(1), and one Si(2) atom. The Mg(1)-Si(1) bond length is 2.57 Å. The Mg(1)-Si(2) bond length is 1.45 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 3-coordinate geometry to one K(1), one Mg(1), and one Si(2) atom. The Si(1)-Si(2) bond length is 1.09 Å. In the second Si site, Si(2) is bonded in a 2-coordinate geometry to one K(1), one Mg(1), and one Si(1) atom.