The material described by SrGa2(SiO4)2 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(7), one O(8), and two equivalent O(6) atoms. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form GaO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. In the second Ga site, Ga(2) is bonded to one O(2), one O(4), one O(7), and one O(8) atom to form GaO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Ga(2)O4 tetrahedra and corners with three equivalent Ga(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Ga(1)O4 tetrahedra and corners with three equivalent Ga(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a trigonal planar geometry to one Sr(1), one Ga(2), and one Si(1) atom. In the second O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(2), and one Si(2) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(1), and one Si(1) atom. In the fourth O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(2), and one Si(2) atom. In the fifth O site, O(6) is bonded to two equivalent Sr(1), one Ga(1), and one Si(2) atom to form distorted edge-sharing OSr2GaSi tetrahedra. In the sixth O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Ga(1), and one Si(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one Ga(2) and one Si(2) atom. In the eighth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Sr(1), one Ga(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrGa2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.505
_cell_length_b   9.330
_cell_length_c   9.330
_cell_angle_alpha   89.729
_cell_angle_beta   82.947
_cell_angle_gamma   82.947
_symmetry_Int_Tables_number   1
_cell_volume   729.233
_cell_formula_units_Z   4
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
  Sr  Sr0  1  0.301  0.438  0.430  1.0
  Sr  Sr1  1  0.199  0.070  0.062  1.0
  Sr  Sr2  1  0.699  0.562  0.570  1.0
  Sr  Sr3  1  0.801  0.930  0.938  1.0
  Ga  Ga4  1  0.120  0.701  0.059  1.0
  Ga  Ga5  1  0.380  0.441  0.799  1.0
  Ga  Ga6  1  0.880  0.299  0.941  1.0
  Ga  Ga7  1  0.620  0.559  0.201  1.0
  Ga  Ga8  1  0.524  0.046  0.293  1.0
  Ga  Ga9  1  0.976  0.207  0.454  1.0
  Ga  Ga10  1  0.476  0.954  0.707  1.0
  Ga  Ga11  1  0.024  0.793  0.546  1.0
  Si  Si12  1  0.493  0.719  0.940  1.0
  Si  Si13  1  0.007  0.560  0.781  1.0
  Si  Si14  1  0.507  0.281  0.060  1.0
  Si  Si15  1  0.993  0.440  0.219  1.0
  Si  Si16  1  0.902  0.935  0.277  1.0
  Si  Si17  1  0.598  0.223  0.565  1.0
  Si  Si18  1  0.098  0.065  0.723  1.0
  Si  Si19  1  0.402  0.777  0.435  1.0
  O  O20  1  0.002  0.677  0.911  1.0
  O  O21  1  0.498  0.589  0.823  1.0
  O  O22  1  0.998  0.323  0.089  1.0
  O  O23  1  0.502  0.411  0.177  1.0
  O  O24  1  0.504  0.185  0.432  1.0
  O  O25  1  0.996  0.068  0.315  1.0
  O  O26  1  0.496  0.815  0.568  1.0
  O  O27  1  0.004  0.932  0.685  1.0
  O  O28  1  0.121  0.554  0.184  1.0
  O  O29  1  0.379  0.316  0.946  1.0
  O  O30  1  0.879  0.446  0.816  1.0
  O  O31  1  0.621  0.684  0.054  1.0
  O  O32  1  0.608  0.093  0.678  1.0
  O  O33  1  0.892  0.822  0.407  1.0
  O  O34  1  0.392  0.907  0.322  1.0
  O  O35  1  0.108  0.178  0.593  1.0
  O  O36  1  0.312  0.768  0.015  1.0
  O  O37  1  0.188  0.485  0.732  1.0
  O  O38  1  0.688  0.232  0.985  1.0
  O  O39  1  0.812  0.515  0.268  1.0
  O  O40  1  0.993  0.125  0.875  1.0
  O  O41  1  0.507  0.625  0.375  1.0
  O  O42  1  0.007  0.875  0.125  1.0
  O  O43  1  0.493  0.375  0.625  1.0
  O  O44  1  0.560  0.858  0.858  1.0
  O  O45  1  0.940  0.642  0.642  1.0
  O  O46  1  0.440  0.142  0.142  1.0
  O  O47  1  0.060  0.358  0.358  1.0
  O  O48  1  0.271  0.019  0.777  1.0
  O  O49  1  0.229  0.723  0.481  1.0
  O  O50  1  0.729  0.981  0.223  1.0
  O  O51  1  0.771  0.277  0.519  1.0
[/CIF]
.
The material described by SrGa2(SiO4)2 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(7), one O(8), and two equivalent O(6) atoms. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form GaO4 tetrahedra that share  a cornercorner with one Si(2)O4 tetrahedra and corners with three equivalent Si(1)O4 tetrahedra. In the second Ga site, Ga(2) is bonded to one O(2), one O(4), one O(7), and one O(8) atom to form GaO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra and corners with three equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Ga(2)O4 tetrahedra and corners with three equivalent Ga(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(2), one O(4), one O(6), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Ga(1)O4 tetrahedra and corners with three equivalent Ga(2)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a trigonal planar geometry to one Sr(1), one Ga(2), and one Si(1) atom. In the second O site, O(8) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(2), and one Si(2) atom. In the third O site, O(1) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(1), and one Si(1) atom. In the fourth O site, O(2) is bonded in a 3-coordinate geometry to one Sr(1), one Ga(2), and one Si(2) atom. In the fifth O site, O(6) is bonded to two equivalent Sr(1), one Ga(1), and one Si(2) atom to form distorted edge-sharing OSr2GaSi tetrahedra. In the sixth O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Sr(1), one Ga(1), and one Si(1) atom. In the seventh O site, O(4) is bonded in a bent 120 degrees geometry to one Ga(2) and one Si(2) atom. In the eighth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Sr(1), one Ga(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrGa2(SiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.505
_cell_length_b   9.330
_cell_length_c   9.330
_cell_angle_alpha   89.729
_cell_angle_beta   82.947
_cell_angle_gamma   82.947
_symmetry_Int_Tables_number   1
_cell_volume   729.233
_cell_formula_units_Z   4
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
  Sr  Sr0  1  0.301  0.438  0.430  1.0
  Sr  Sr1  1  0.199  0.070  0.062  1.0
  Sr  Sr2  1  0.699  0.562  0.570  1.0
  Sr  Sr3  1  0.801  0.930  0.938  1.0
  Ga  Ga4  1  0.120  0.701  0.059  1.0
  Ga  Ga5  1  0.380  0.441  0.799  1.0
  Ga  Ga6  1  0.880  0.299  0.941  1.0
  Ga  Ga7  1  0.620  0.559  0.201  1.0
  Ga  Ga8  1  0.524  0.046  0.293  1.0
  Ga  Ga9  1  0.976  0.207  0.454  1.0
  Ga  Ga10  1  0.476  0.954  0.707  1.0
  Ga  Ga11  1  0.024  0.793  0.546  1.0
  Si  Si12  1  0.493  0.719  0.940  1.0
  Si  Si13  1  0.007  0.560  0.781  1.0
  Si  Si14  1  0.507  0.281  0.060  1.0
  Si  Si15  1  0.993  0.440  0.219  1.0
  Si  Si16  1  0.902  0.935  0.277  1.0
  Si  Si17  1  0.598  0.223  0.565  1.0
  Si  Si18  1  0.098  0.065  0.723  1.0
  Si  Si19  1  0.402  0.777  0.435  1.0
  O  O20  1  0.002  0.677  0.911  1.0
  O  O21  1  0.498  0.589  0.823  1.0
  O  O22  1  0.998  0.323  0.089  1.0
  O  O23  1  0.502  0.411  0.177  1.0
  O  O24  1  0.504  0.185  0.432  1.0
  O  O25  1  0.996  0.068  0.315  1.0
  O  O26  1  0.496  0.815  0.568  1.0
  O  O27  1  0.004  0.932  0.685  1.0
  O  O28  1  0.121  0.554  0.184  1.0
  O  O29  1  0.379  0.316  0.946  1.0
  O  O30  1  0.879  0.446  0.816  1.0
  O  O31  1  0.621  0.684  0.054  1.0
  O  O32  1  0.608  0.093  0.678  1.0
  O  O33  1  0.892  0.822  0.407  1.0
  O  O34  1  0.392  0.907  0.322  1.0
  O  O35  1  0.108  0.178  0.593  1.0
  O  O36  1  0.312  0.768  0.015  1.0
  O  O37  1  0.188  0.485  0.732  1.0
  O  O38  1  0.688  0.232  0.985  1.0
  O  O39  1  0.812  0.515  0.268  1.0
  O  O40  1  0.993  0.125  0.875  1.0
  O  O41  1  0.507  0.625  0.375  1.0
  O  O42  1  0.007  0.875  0.125  1.0
  O  O43  1  0.493  0.375  0.625  1.0
  O  O44  1  0.560  0.858  0.858  1.0
  O  O45  1  0.940  0.642  0.642  1.0
  O  O46  1  0.440  0.142  0.142  1.0
  O  O47  1  0.060  0.358  0.358  1.0
  O  O48  1  0.271  0.019  0.777  1.0
  O  O49  1  0.229  0.723  0.481  1.0
  O  O50  1  0.729  0.981  0.223  1.0
  O  O51  1  0.771  0.277  0.519  1.0
[/CIF]
.