The compound described by MgHo2Cu(SiO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Ho(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(3), and two equivalent O(6) atoms. Cu(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(4) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ho(1), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ho(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ho(1), one Cu(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to two equivalent Ho(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2MgCu(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.254
_cell_length_b   7.298
_cell_length_c   7.913
_cell_angle_alpha   62.640
_cell_angle_beta   84.763
_cell_angle_gamma   78.499
_symmetry_Int_Tables_number   1
_cell_volume   264.057
_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
  Ho  Ho0  1  0.003  0.792  0.414  1.0
  Ho  Ho1  1  0.997  0.208  0.586  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Si  Si4  1  0.593  0.578  0.227  1.0
  Si  Si5  1  0.407  0.422  0.773  1.0
  Si  Si6  1  0.413  0.193  0.229  1.0
  Si  Si7  1  0.587  0.807  0.771  1.0
  O  O8  1  0.346  0.754  0.229  1.0
  O  O9  1  0.654  0.246  0.771  1.0
  O  O10  1  0.314  0.318  0.002  1.0
  O  O11  1  0.686  0.682  0.998  1.0
  O  O12  1  0.167  0.459  0.639  1.0
  O  O13  1  0.833  0.541  0.361  1.0
  O  O14  1  0.341  0.984  0.772  1.0
  O  O15  1  0.659  0.016  0.228  1.0
  O  O16  1  0.506  0.352  0.295  1.0
  O  O17  1  0.494  0.648  0.705  1.0
  O  O18  1  0.175  0.095  0.365  1.0
  O  O19  1  0.825  0.905  0.635  1.0
[/CIF]
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The compound described by MgHo2Cu(SiO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Ho(1) is bonded in a 6-coordinate geometry to one O(1), one O(4), two equivalent O(3), and two equivalent O(6) atoms. Cu(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(4) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing SiO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ho(1), one Cu(1), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Si(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ho(1) and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ho(1), one Cu(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to two equivalent Ho(1) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ho2MgCu(SiO3)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.254
_cell_length_b   7.298
_cell_length_c   7.913
_cell_angle_alpha   62.640
_cell_angle_beta   84.763
_cell_angle_gamma   78.499
_symmetry_Int_Tables_number   1
_cell_volume   264.057
_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
  Ho  Ho0  1  0.003  0.792  0.414  1.0
  Ho  Ho1  1  0.997  0.208  0.586  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Si  Si4  1  0.593  0.578  0.227  1.0
  Si  Si5  1  0.407  0.422  0.773  1.0
  Si  Si6  1  0.413  0.193  0.229  1.0
  Si  Si7  1  0.587  0.807  0.771  1.0
  O  O8  1  0.346  0.754  0.229  1.0
  O  O9  1  0.654  0.246  0.771  1.0
  O  O10  1  0.314  0.318  0.002  1.0
  O  O11  1  0.686  0.682  0.998  1.0
  O  O12  1  0.167  0.459  0.639  1.0
  O  O13  1  0.833  0.541  0.361  1.0
  O  O14  1  0.341  0.984  0.772  1.0
  O  O15  1  0.659  0.016  0.228  1.0
  O  O16  1  0.506  0.352  0.295  1.0
  O  O17  1  0.494  0.648  0.705  1.0
  O  O18  1  0.175  0.095  0.365  1.0
  O  O19  1  0.825  0.905  0.635  1.0
[/CIF]
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