The material described by Sr4MgTm8O16 crystallizes in the monoclinic Pm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(11), two equivalent O(14), and two equivalent O(3) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Mg(1), one O(16), one O(7), two equivalent O(12), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one O(13), one O(8), two equivalent O(1), and two equivalent O(9) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(7), two equivalent O(10), two equivalent O(15), and two equivalent O(2) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Sr(2), one O(5), and two equivalent O(13) atoms. There are eight inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(11), one O(16), two equivalent O(12), and two equivalent O(6) atoms to form a mixture of distorted edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. In the second Tm site, Tm(2) is bonded to one O(12), one O(15), two equivalent O(11), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 51-59°. In the third Tm site, Tm(3) is bonded to one O(14), one O(9), two equivalent O(10), and two equivalent O(8) atoms to form TmO6 octahedra that share corners with two equivalent Tm(5)O6 octahedra, corners with two equivalent Tm(7)O6 octahedra, edges with two equivalent Tm(3)O6 octahedra, and edges with two equivalent Tm(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-60°. In the fourth Tm site, Tm(4) is bonded to one O(10), two equivalent O(7), and two equivalent O(9) atoms to form TmO5 square pyramids that share corners with two equivalent Tm(6)O6 octahedra, edges with two equivalent Tm(3)O6 octahedra, and edges with two equivalent Tm(4)O5 square pyramids. The corner-sharing octahedral tilt angles are 49°. In the fifth Tm site, Tm(5) is bonded to one O(4), one O(8), two equivalent O(16), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. In the sixth Tm site, Tm(6) is bonded to one O(3), one O(7), two equivalent O(15), and two equivalent O(4) atoms to form TmO6 octahedra that share corners with two equivalent Tm(2)O6 octahedra, corners with two equivalent Tm(4)O5 square pyramids, edges with two equivalent Tm(5)O6 octahedra, and edges with two equivalent Tm(6)O6 octahedra. The corner-sharing octahedral tilt angles are 59°. In the seventh Tm site, Tm(7) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(14) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 53-60°. In the eighth Tm site, Tm(8) is bonded to one O(1), one O(5), two equivalent O(13), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(3), one Tm(8), and two equivalent Tm(7) atoms to form distorted OSr2Tm3 square pyramids that share corners with two equivalent O(9)Sr2Tm3 square pyramids,  a cornercorner with one O(5)Tm3Mg tetrahedra, corners with two equivalent O(6)SrTm3 trigonal pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(9)Sr2Tm3 square pyramid, edges with two equivalent O(1)Sr2Tm3 square pyramids, and edges with two equivalent O(2)Sr2Tm3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Sr(4), one Tm(7), and two equivalent Tm(8) atoms to form distorted OSr2Tm3 trigonal bipyramids that share corners with two equivalent O(10)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra,  a cornercorner with one O(6)SrTm3 trigonal pyramid, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids,  an edgeedge with one O(10)Sr2Tm3 square pyramid, edges with two equivalent O(1)Sr2Tm3 square pyramids, and edges with two equivalent O(2)Sr2Tm3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Sr(1), one Tm(6), and two equivalent Tm(5) atoms to form distorted OSr2Tm3 square pyramids that share corners with two equivalent O(11)Sr2Tm3 square pyramids,  a cornercorner with one O(7)Sr2Tm3 trigonal pyramid, corners with two equivalent O(6)SrTm3 trigonal pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(11)Sr2Tm3 square pyramid, edges with two equivalent O(3)Sr2Tm3 square pyramids, and edges with two equivalent O(4)Sr2Tm3 square pyramids. In the fourth O site, O(4) is bonded to two equivalent Sr(2), one Tm(5), and two equivalent Tm(6) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids,  a cornercorner with one O(8)SrTm3 trigonal pyramid, edges with two equivalent O(3)Sr2Tm3 square pyramids, edges with two equivalent O(4)Sr2Tm3 square pyramids,  an edgeedge with one O(12)Sr2Tm3 trigonal bipyramid, and edges with two equivalent O(7)Sr2Tm3 trigonal pyramids. In the fifth O site, O(5) is bonded to one Mg(1), one Tm(8), and two equivalent Tm(2) atoms to form distorted OTm3Mg tetrahedra that share  a cornercorner with one O(1)Sr2Tm3 square pyramid, corners with two equivalent O(11)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra, corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(2)Sr2Tm3 trigonal bipyramids, and  an edgeedge with one O(11)Sr2Tm3 square pyramid. In the sixth O site, O(6) is bonded to one Sr(1), one Tm(7), and two equivalent Tm(1) atoms to form distorted OSrTm3 trigonal pyramids that share corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(3)Sr2Tm3 square pyramids,  a cornercorner with one O(2)Sr2Tm3 trigonal bipyramid, corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(6)SrTm3 trigonal pyramids, edges with two equivalent O(11)Sr2Tm3 square pyramids, and  an edgeedge with one O(12)Sr2Tm3 trigonal bipyramid. In the seventh O site, O(7) is bonded to one Sr(2), one Sr(4), one Tm(6), and two equivalent Tm(4) atoms to form a mixture of distorted edge and corner-sharing OSr2Tm3 trigonal pyramids. In the eighth O site, O(8) is bonded to one Sr(3), one Tm(5), and two equivalent Tm(3) atoms to form distorted OSrTm3 trigonal pyramids that share  a cornercorner with one O(4)Sr2Tm3 square pyramid, corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(10)Sr2Tm3 square pyramids, corners with two equivalent O(3)Sr2Tm3 square pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(10)Sr2Tm3 square pyramid, and edges with two equivalent O(9)Sr2Tm3 square pyramids. In the ninth O site, O(9) is bonded to two equivalent Sr(3), one Tm(3), and two equivalent Tm(4) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids,  an edgeedge with one O(1)Sr2Tm3 square pyramid, edges with two equivalent O(10)Sr2Tm3 square pyramids, edges with two equivalent O(9)Sr2Tm3 square pyramids,  an edgeedge with one O(7)Sr2Tm3 trigonal pyramid, and edges with two equivalent O(8)SrTm3 trigonal pyramids. In the tenth O site, O(10) is bonded to two equivalent Sr(4), one Tm(4), and two equivalent Tm(3) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(2)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids, edges with two equivalent O(10)Sr2Tm3 square pyramids, edges with two equivalent O(9)Sr2Tm3 square pyramids,  an edgeedge with one O(2)Sr2Tm3 trigonal bipyramid,  an edgeedge with one O(8)SrTm3 trigonal pyramid, and edges with two equivalent O(7)Sr2Tm3 trigonal pyramids. In the eleventh O site, O(11) is bonded to two equivalent Sr(1), one Tm(1), and two equivalent Tm(2) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(3)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra,  an edgeedge with one O(3)Sr2Tm3 square pyramid, edges with two equivalent O(11)Sr2Tm3 square pyramids,  an edgeedge with one O(5)Tm3Mg tetrahedra, edges with two equivalent O(12)Sr2Tm3 trigonal bipyramids, and edges with two equivalent O(6)SrTm3 trigonal pyramids. In the twelfth O site, O(12) is bonded to two equivalent Sr(2), one Tm(2), and two equivalent Tm(1) atoms to form distorted OSr2Tm3 trigonal bipyramids that share corners with two equivalent O(4)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids, corners with two equivalent O(6)SrTm3 trigonal pyramids,  an edgeedge with one O(4)Sr2Tm3 square pyramid, edges with two equivalent O(11)Sr2Tm3 square pyramids, edges with two equivalent O(12)Sr2Tm3 trigonal bipyramids, and  an edgeedge with one O(6)SrTm3 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(3), two equivalent Mg(1), and two equivalent Tm(8) atoms. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one Tm(3), and two equivalent Tm(7) atoms. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to two equivalent Sr(4), one Tm(2), and two equivalent Tm(6) atoms. In the sixteenth O site, O(16) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Tm(1), and two equivalent Tm(5) atoms. is represented by the CIF card [CIF]
data_Sr4Tm8MgO16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.354
_cell_length_b   10.748
_cell_length_c   12.158
_cell_angle_alpha   95.023
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   436.621
_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
  Sr  Sr0  1  0.750  0.762  0.364  1.0
  Sr  Sr1  1  0.250  0.300  0.580  1.0
  Sr  Sr2  1  0.750  0.257  0.094  1.0
  Sr  Sr3  1  0.250  0.725  0.856  1.0
  Tm  Tm4  1  0.250  0.072  0.396  1.0
  Tm  Tm5  1  0.750  0.945  0.619  1.0
  Tm  Tm6  1  0.250  0.568  0.099  1.0
  Tm  Tm7  1  0.750  0.437  0.860  1.0
  Tm  Tm8  1  0.750  0.441  0.366  1.0
  Tm  Tm9  1  0.250  0.606  0.596  1.0
  Tm  Tm10  1  0.750  0.906  0.137  1.0
  Tm  Tm11  1  0.250  0.010  0.926  1.0
  Mg  Mg12  1  0.250  0.192  0.795  1.0
  O  O13  1  0.250  0.050  0.104  1.0
  O  O14  1  0.750  0.879  0.947  1.0
  O  O15  1  0.250  0.593  0.407  1.0
  O  O16  1  0.750  0.465  0.552  1.0
  O  O17  1  0.250  0.999  0.737  1.0
  O  O18  1  0.750  0.986  0.305  1.0
  O  O19  1  0.250  0.521  0.766  1.0
  O  O20  1  0.750  0.488  0.191  1.0
  O  O21  1  0.250  0.385  0.987  1.0
  O  O22  1  0.750  0.611  0.976  1.0
  O  O23  1  0.250  0.895  0.493  1.0
  O  O24  1  0.750  0.123  0.520  1.0
  O  O25  1  0.750  0.146  0.908  1.0
  O  O26  1  0.250  0.774  0.176  1.0
  O  O27  1  0.750  0.735  0.656  1.0
  O  O28  1  0.250  0.299  0.360  1.0
[/CIF]
.
The material described by Sr4MgTm8O16 crystallizes in the monoclinic Pm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(11), two equivalent O(14), and two equivalent O(3) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Mg(1), one O(16), one O(7), two equivalent O(12), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a 6-coordinate geometry to one O(13), one O(8), two equivalent O(1), and two equivalent O(9) atoms. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(7), two equivalent O(10), two equivalent O(15), and two equivalent O(2) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Sr(2), one O(5), and two equivalent O(13) atoms. There are eight inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to one O(11), one O(16), two equivalent O(12), and two equivalent O(6) atoms to form a mixture of distorted edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. In the second Tm site, Tm(2) is bonded to one O(12), one O(15), two equivalent O(11), and two equivalent O(5) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 51-59°. In the third Tm site, Tm(3) is bonded to one O(14), one O(9), two equivalent O(10), and two equivalent O(8) atoms to form TmO6 octahedra that share corners with two equivalent Tm(5)O6 octahedra, corners with two equivalent Tm(7)O6 octahedra, edges with two equivalent Tm(3)O6 octahedra, and edges with two equivalent Tm(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-60°. In the fourth Tm site, Tm(4) is bonded to one O(10), two equivalent O(7), and two equivalent O(9) atoms to form TmO5 square pyramids that share corners with two equivalent Tm(6)O6 octahedra, edges with two equivalent Tm(3)O6 octahedra, and edges with two equivalent Tm(4)O5 square pyramids. The corner-sharing octahedral tilt angles are 49°. In the fifth Tm site, Tm(5) is bonded to one O(4), one O(8), two equivalent O(16), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. In the sixth Tm site, Tm(6) is bonded to one O(3), one O(7), two equivalent O(15), and two equivalent O(4) atoms to form TmO6 octahedra that share corners with two equivalent Tm(2)O6 octahedra, corners with two equivalent Tm(4)O5 square pyramids, edges with two equivalent Tm(5)O6 octahedra, and edges with two equivalent Tm(6)O6 octahedra. The corner-sharing octahedral tilt angles are 59°. In the seventh Tm site, Tm(7) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(14) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles range from 53-60°. In the eighth Tm site, Tm(8) is bonded to one O(1), one O(5), two equivalent O(13), and two equivalent O(2) atoms to form a mixture of edge and corner-sharing TmO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(3), one Tm(8), and two equivalent Tm(7) atoms to form distorted OSr2Tm3 square pyramids that share corners with two equivalent O(9)Sr2Tm3 square pyramids,  a cornercorner with one O(5)Tm3Mg tetrahedra, corners with two equivalent O(6)SrTm3 trigonal pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(9)Sr2Tm3 square pyramid, edges with two equivalent O(1)Sr2Tm3 square pyramids, and edges with two equivalent O(2)Sr2Tm3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Sr(4), one Tm(7), and two equivalent Tm(8) atoms to form distorted OSr2Tm3 trigonal bipyramids that share corners with two equivalent O(10)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra,  a cornercorner with one O(6)SrTm3 trigonal pyramid, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids,  an edgeedge with one O(10)Sr2Tm3 square pyramid, edges with two equivalent O(1)Sr2Tm3 square pyramids, and edges with two equivalent O(2)Sr2Tm3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Sr(1), one Tm(6), and two equivalent Tm(5) atoms to form distorted OSr2Tm3 square pyramids that share corners with two equivalent O(11)Sr2Tm3 square pyramids,  a cornercorner with one O(7)Sr2Tm3 trigonal pyramid, corners with two equivalent O(6)SrTm3 trigonal pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(11)Sr2Tm3 square pyramid, edges with two equivalent O(3)Sr2Tm3 square pyramids, and edges with two equivalent O(4)Sr2Tm3 square pyramids. In the fourth O site, O(4) is bonded to two equivalent Sr(2), one Tm(5), and two equivalent Tm(6) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids,  a cornercorner with one O(8)SrTm3 trigonal pyramid, edges with two equivalent O(3)Sr2Tm3 square pyramids, edges with two equivalent O(4)Sr2Tm3 square pyramids,  an edgeedge with one O(12)Sr2Tm3 trigonal bipyramid, and edges with two equivalent O(7)Sr2Tm3 trigonal pyramids. In the fifth O site, O(5) is bonded to one Mg(1), one Tm(8), and two equivalent Tm(2) atoms to form distorted OTm3Mg tetrahedra that share  a cornercorner with one O(1)Sr2Tm3 square pyramid, corners with two equivalent O(11)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra, corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(2)Sr2Tm3 trigonal bipyramids, and  an edgeedge with one O(11)Sr2Tm3 square pyramid. In the sixth O site, O(6) is bonded to one Sr(1), one Tm(7), and two equivalent Tm(1) atoms to form distorted OSrTm3 trigonal pyramids that share corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(3)Sr2Tm3 square pyramids,  a cornercorner with one O(2)Sr2Tm3 trigonal bipyramid, corners with two equivalent O(12)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(6)SrTm3 trigonal pyramids, edges with two equivalent O(11)Sr2Tm3 square pyramids, and  an edgeedge with one O(12)Sr2Tm3 trigonal bipyramid. In the seventh O site, O(7) is bonded to one Sr(2), one Sr(4), one Tm(6), and two equivalent Tm(4) atoms to form a mixture of distorted edge and corner-sharing OSr2Tm3 trigonal pyramids. In the eighth O site, O(8) is bonded to one Sr(3), one Tm(5), and two equivalent Tm(3) atoms to form distorted OSrTm3 trigonal pyramids that share  a cornercorner with one O(4)Sr2Tm3 square pyramid, corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(10)Sr2Tm3 square pyramids, corners with two equivalent O(3)Sr2Tm3 square pyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids,  an edgeedge with one O(10)Sr2Tm3 square pyramid, and edges with two equivalent O(9)Sr2Tm3 square pyramids. In the ninth O site, O(9) is bonded to two equivalent Sr(3), one Tm(3), and two equivalent Tm(4) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(1)Sr2Tm3 square pyramids, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids,  an edgeedge with one O(1)Sr2Tm3 square pyramid, edges with two equivalent O(10)Sr2Tm3 square pyramids, edges with two equivalent O(9)Sr2Tm3 square pyramids,  an edgeedge with one O(7)Sr2Tm3 trigonal pyramid, and edges with two equivalent O(8)SrTm3 trigonal pyramids. In the tenth O site, O(10) is bonded to two equivalent Sr(4), one Tm(4), and two equivalent Tm(3) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(2)Sr2Tm3 trigonal bipyramids, corners with two equivalent O(8)SrTm3 trigonal pyramids, edges with two equivalent O(10)Sr2Tm3 square pyramids, edges with two equivalent O(9)Sr2Tm3 square pyramids,  an edgeedge with one O(2)Sr2Tm3 trigonal bipyramid,  an edgeedge with one O(8)SrTm3 trigonal pyramid, and edges with two equivalent O(7)Sr2Tm3 trigonal pyramids. In the eleventh O site, O(11) is bonded to two equivalent Sr(1), one Tm(1), and two equivalent Tm(2) atoms to form OSr2Tm3 square pyramids that share corners with two equivalent O(3)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra,  an edgeedge with one O(3)Sr2Tm3 square pyramid, edges with two equivalent O(11)Sr2Tm3 square pyramids,  an edgeedge with one O(5)Tm3Mg tetrahedra, edges with two equivalent O(12)Sr2Tm3 trigonal bipyramids, and edges with two equivalent O(6)SrTm3 trigonal pyramids. In the twelfth O site, O(12) is bonded to two equivalent Sr(2), one Tm(2), and two equivalent Tm(1) atoms to form distorted OSr2Tm3 trigonal bipyramids that share corners with two equivalent O(4)Sr2Tm3 square pyramids, corners with two equivalent O(5)Tm3Mg tetrahedra, corners with two equivalent O(7)Sr2Tm3 trigonal pyramids, corners with two equivalent O(6)SrTm3 trigonal pyramids,  an edgeedge with one O(4)Sr2Tm3 square pyramid, edges with two equivalent O(11)Sr2Tm3 square pyramids, edges with two equivalent O(12)Sr2Tm3 trigonal bipyramids, and  an edgeedge with one O(6)SrTm3 trigonal pyramid. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(3), two equivalent Mg(1), and two equivalent Tm(8) atoms. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to two equivalent Sr(1), one Tm(3), and two equivalent Tm(7) atoms. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to two equivalent Sr(4), one Tm(2), and two equivalent Tm(6) atoms. In the sixteenth O site, O(16) is bonded in a rectangular see-saw-like geometry to one Sr(2), one Tm(1), and two equivalent Tm(5) atoms. is represented by the CIF card [CIF]
data_Sr4Tm8MgO16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.354
_cell_length_b   10.748
_cell_length_c   12.158
_cell_angle_alpha   95.023
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   436.621
_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
  Sr  Sr0  1  0.750  0.762  0.364  1.0
  Sr  Sr1  1  0.250  0.300  0.580  1.0
  Sr  Sr2  1  0.750  0.257  0.094  1.0
  Sr  Sr3  1  0.250  0.725  0.856  1.0
  Tm  Tm4  1  0.250  0.072  0.396  1.0
  Tm  Tm5  1  0.750  0.945  0.619  1.0
  Tm  Tm6  1  0.250  0.568  0.099  1.0
  Tm  Tm7  1  0.750  0.437  0.860  1.0
  Tm  Tm8  1  0.750  0.441  0.366  1.0
  Tm  Tm9  1  0.250  0.606  0.596  1.0
  Tm  Tm10  1  0.750  0.906  0.137  1.0
  Tm  Tm11  1  0.250  0.010  0.926  1.0
  Mg  Mg12  1  0.250  0.192  0.795  1.0
  O  O13  1  0.250  0.050  0.104  1.0
  O  O14  1  0.750  0.879  0.947  1.0
  O  O15  1  0.250  0.593  0.407  1.0
  O  O16  1  0.750  0.465  0.552  1.0
  O  O17  1  0.250  0.999  0.737  1.0
  O  O18  1  0.750  0.986  0.305  1.0
  O  O19  1  0.250  0.521  0.766  1.0
  O  O20  1  0.750  0.488  0.191  1.0
  O  O21  1  0.250  0.385  0.987  1.0
  O  O22  1  0.750  0.611  0.976  1.0
  O  O23  1  0.250  0.895  0.493  1.0
  O  O24  1  0.750  0.123  0.520  1.0
  O  O25  1  0.750  0.146  0.908  1.0
  O  O26  1  0.250  0.774  0.176  1.0
  O  O27  1  0.750  0.735  0.656  1.0
  O  O28  1  0.250  0.299  0.360  1.0
[/CIF]
.