The material structure described by Sr3Nd4O9 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(11), one O(14), one O(5), one O(6), and one O(8) atom to form SrO5 trigonal bipyramids that share corners with two equivalent Nd(4)O5 trigonal bipyramids and  an edgeedge with one Sr(5)O6 octahedra. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(10), one O(13), one O(3), one O(4), one O(5), and one O(9) atom. In the third Sr site, Sr(3) is bonded in a 7-coordinate geometry to one O(10), one O(11), one O(13), one O(15), one O(5), one O(6), and one O(8) atom. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(12), one O(17), one O(2), one O(4), and one O(7) atom. In the fifth Sr site, Sr(5) is bonded to one O(11), one O(15), one O(16), one O(17), one O(18), and one O(8) atom to form distorted SrO6 octahedra that share corners with two equivalent Nd(4)O5 trigonal bipyramids and  an edgeedge with one Sr(1)O5 trigonal bipyramid. In the sixth Sr site, Sr(6) is bonded in a 6-coordinate geometry to one O(15), one O(17), one O(18), one O(2), one O(3), and one O(4) atom. There are eight inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 5-coordinate geometry to one O(1), one O(13), one O(14), one O(15), one O(16), and one O(6) atom. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(16), one O(18), and one O(6) atom. In the third Nd site, Nd(3) is bonded in a 5-coordinate geometry to one O(12), one O(17), one O(3), one O(7), one O(8), and one O(9) atom. In the fourth Nd site, Nd(4) is bonded to one O(11), one O(12), one O(3), one O(8), and one O(9) atom to form distorted NdO5 trigonal bipyramids that share corners with two equivalent Sr(5)O6 octahedra and corners with two equivalent Sr(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 16-84°. In the fifth Nd site, Nd(5) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(13), one O(16), one O(5), and one O(7) atom. In the sixth Nd site, Nd(6) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), and one O(5) atom. In the seventh Nd site, Nd(7) is bonded in a 7-coordinate geometry to one O(12), one O(14), one O(15), one O(17), one O(18), one O(2), and one O(8) atom. In the eighth Nd site, Nd(8) is bonded in a 7-coordinate geometry to one O(1), one O(12), one O(13), one O(17), one O(4), one O(7), and one O(9) atom. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Sr(4), one Nd(1), one Nd(2), one Nd(5), one Nd(6), and one Nd(8) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Sr(4), one Sr(6), one Nd(6), and one Nd(7) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(6), one Nd(3), one Nd(4), and one Nd(6) atom. In the fourth O site, O(4) is bonded to one Sr(2), one Sr(4), one Sr(6), one Nd(6), and one Nd(8) atom to form OSr3Nd2 square pyramids that share  a cornercorner with one O(18)Sr2Nd2 trigonal pyramid, corners with two equivalent O(9)SrNd3 trigonal pyramids, and  an edgeedge with one O(7)SrNd3 trigonal pyramid. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Nd(5), and one Nd(6) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), one Nd(1), and one Nd(2) atom. In the seventh O site, O(7) is bonded to one Sr(4), one Nd(3), one Nd(5), and one Nd(8) atom to form distorted OSrNd3 trigonal pyramids that share  a cornercorner with one O(16)SrNd3 tetrahedra,  an edgeedge with one O(4)Sr3Nd2 square pyramid, and  an edgeedge with one O(9)SrNd3 trigonal pyramid. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Nd(3), one Nd(4), and one Nd(7) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Nd(3), one Nd(4), and one Nd(8) atom to form OSrNd3 trigonal pyramids that share  a cornercorner with one O(11)Sr3Nd2 square pyramid, corners with two equivalent O(4)Sr3Nd2 square pyramids, and  an edgeedge with one O(7)SrNd3 trigonal pyramid. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(3), one Sr(4), one Nd(2), and one Nd(6) atom. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(3), one Sr(5), one Nd(2), and one Nd(4) atom to form distorted OSr3Nd2 square pyramids that share corners with two equivalent O(16)SrNd3 tetrahedra,  a cornercorner with one O(9)SrNd3 trigonal pyramid, and corners with two equivalent O(18)Sr2Nd2 trigonal pyramids. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to one Sr(4), one Nd(3), one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(3), one Nd(1), one Nd(5), and one Nd(8) atom. In the fourteenth O site, O(14) is bonded in a distorted see-saw-like geometry to one Sr(1), one Nd(1), one Nd(2), and one Nd(7) atom. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to one Sr(3), one Sr(5), one Sr(6), one Nd(1), and one Nd(7) atom. In the sixteenth O site, O(16) is bonded to one Sr(5), one Nd(1), one Nd(2), and one Nd(5) atom to form OSrNd3 tetrahedra that share corners with two equivalent O(11)Sr3Nd2 square pyramids,  a cornercorner with one O(7)SrNd3 trigonal pyramid, and  an edgeedge with one O(18)Sr2Nd2 trigonal pyramid. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Sr(4), one Sr(5), one Sr(6), one Nd(3), one Nd(7), and one Nd(8) atom. In the eighteenth O site, O(18) is bonded to one Sr(5), one Sr(6), one Nd(2), and one Nd(7) atom to form OSr2Nd2 trigonal pyramids that share  a cornercorner with one O(4)Sr3Nd2 square pyramid, corners with two equivalent O(11)Sr3Nd2 square pyramids, and  an edgeedge with one O(16)SrNd3 tetrahedra. is represented by the CIF card [CIF]
data_Sr3Nd4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.668
_cell_length_b   7.111
_cell_length_c   10.056
_cell_angle_alpha   99.701
_cell_angle_beta   96.860
_cell_angle_gamma   107.928
_symmetry_Int_Tables_number   1
_cell_volume   571.507
_cell_formula_units_Z   2
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  0.264  0.743  0.021  1.0
  Sr  Sr1  1  0.267  0.343  0.611  1.0
  Sr  Sr2  1  0.408  0.358  0.934  1.0
  Sr  Sr3  1  0.875  0.008  0.565  1.0
  Sr  Sr4  1  0.638  0.085  0.120  1.0
  Sr  Sr5  1  0.974  0.407  0.332  1.0
  Nd  Nd6  1  0.848  0.436  0.926  1.0
  Nd  Nd7  1  0.024  0.047  0.966  1.0
  Nd  Nd8  1  0.455  0.898  0.398  1.0
  Nd  Nd9  1  0.418  0.409  0.290  1.0
  Nd  Nd10  1  0.612  0.792  0.749  1.0
  Nd  Nd11  1  0.131  0.761  0.648  1.0
  Nd  Nd12  1  0.841  0.789  0.233  1.0
  Nd  Nd13  1  0.697  0.378  0.569  1.0
  O  O14  1  0.896  0.766  0.743  1.0
  O  O15  1  0.012  0.800  0.429  1.0
  O  O16  1  0.270  0.566  0.418  1.0
  O  O17  1  0.980  0.393  0.589  1.0
  O  O18  1  0.343  0.681  0.787  1.0
  O  O19  1  0.107  0.391  0.974  1.0
  O  O20  1  0.605  0.012  0.612  1.0
  O  O21  1  0.494  0.712  0.175  1.0
  O  O22  1  0.412  0.204  0.444  1.0
  O  O23  1  0.198  0.094  0.753  1.0
  O  O24  1  0.351  0.131  0.092  1.0
  O  O25  1  0.643  0.620  0.457  1.0
  O  O26  1  0.603  0.451  0.776  1.0
  O  O27  1  0.994  0.749  0.057  1.0
  O  O28  1  0.732  0.440  0.121  1.0
  O  O29  1  0.758  0.071  0.910  1.0
  O  O30  1  0.713  0.112  0.370  1.0
  O  O31  1  0.937  0.099  0.177  1.0
[/CIF]
.
The material structure described by Sr3Nd4O9 crystallizes in the triclinic P1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(11), one O(14), one O(5), one O(6), and one O(8) atom to form SrO5 trigonal bipyramids that share corners with two equivalent Nd(4)O5 trigonal bipyramids and  an edgeedge with one Sr(5)O6 octahedra. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(10), one O(13), one O(3), one O(4), one O(5), and one O(9) atom. In the third Sr site, Sr(3) is bonded in a 7-coordinate geometry to one O(10), one O(11), one O(13), one O(15), one O(5), one O(6), and one O(8) atom. In the fourth Sr site, Sr(4) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(12), one O(17), one O(2), one O(4), and one O(7) atom. In the fifth Sr site, Sr(5) is bonded to one O(11), one O(15), one O(16), one O(17), one O(18), and one O(8) atom to form distorted SrO6 octahedra that share corners with two equivalent Nd(4)O5 trigonal bipyramids and  an edgeedge with one Sr(1)O5 trigonal bipyramid. In the sixth Sr site, Sr(6) is bonded in a 6-coordinate geometry to one O(15), one O(17), one O(18), one O(2), one O(3), and one O(4) atom. There are eight inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a 5-coordinate geometry to one O(1), one O(13), one O(14), one O(15), one O(16), and one O(6) atom. In the second Nd site, Nd(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(11), one O(14), one O(16), one O(18), and one O(6) atom. In the third Nd site, Nd(3) is bonded in a 5-coordinate geometry to one O(12), one O(17), one O(3), one O(7), one O(8), and one O(9) atom. In the fourth Nd site, Nd(4) is bonded to one O(11), one O(12), one O(3), one O(8), and one O(9) atom to form distorted NdO5 trigonal bipyramids that share corners with two equivalent Sr(5)O6 octahedra and corners with two equivalent Sr(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 16-84°. In the fifth Nd site, Nd(5) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(13), one O(16), one O(5), and one O(7) atom. In the sixth Nd site, Nd(6) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), and one O(5) atom. In the seventh Nd site, Nd(7) is bonded in a 7-coordinate geometry to one O(12), one O(14), one O(15), one O(17), one O(18), one O(2), and one O(8) atom. In the eighth Nd site, Nd(8) is bonded in a 7-coordinate geometry to one O(1), one O(12), one O(13), one O(17), one O(4), one O(7), and one O(9) atom. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Sr(4), one Nd(1), one Nd(2), one Nd(5), one Nd(6), and one Nd(8) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Sr(4), one Sr(6), one Nd(6), and one Nd(7) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(6), one Nd(3), one Nd(4), and one Nd(6) atom. In the fourth O site, O(4) is bonded to one Sr(2), one Sr(4), one Sr(6), one Nd(6), and one Nd(8) atom to form OSr3Nd2 square pyramids that share  a cornercorner with one O(18)Sr2Nd2 trigonal pyramid, corners with two equivalent O(9)SrNd3 trigonal pyramids, and  an edgeedge with one O(7)SrNd3 trigonal pyramid. In the fifth O site, O(5) is bonded in a 5-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Nd(5), and one Nd(6) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Sr(3), one Nd(1), and one Nd(2) atom. In the seventh O site, O(7) is bonded to one Sr(4), one Nd(3), one Nd(5), and one Nd(8) atom to form distorted OSrNd3 trigonal pyramids that share  a cornercorner with one O(16)SrNd3 tetrahedra,  an edgeedge with one O(4)Sr3Nd2 square pyramid, and  an edgeedge with one O(9)SrNd3 trigonal pyramid. In the eighth O site, O(8) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(3), one Sr(5), one Nd(3), one Nd(4), and one Nd(7) atom. In the ninth O site, O(9) is bonded to one Sr(2), one Nd(3), one Nd(4), and one Nd(8) atom to form OSrNd3 trigonal pyramids that share  a cornercorner with one O(11)Sr3Nd2 square pyramid, corners with two equivalent O(4)Sr3Nd2 square pyramids, and  an edgeedge with one O(7)SrNd3 trigonal pyramid. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(3), one Sr(4), one Nd(2), and one Nd(6) atom. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(3), one Sr(5), one Nd(2), and one Nd(4) atom to form distorted OSr3Nd2 square pyramids that share corners with two equivalent O(16)SrNd3 tetrahedra,  a cornercorner with one O(9)SrNd3 trigonal pyramid, and corners with two equivalent O(18)Sr2Nd2 trigonal pyramids. In the twelfth O site, O(12) is bonded in a 6-coordinate geometry to one Sr(4), one Nd(3), one Nd(4), one Nd(5), one Nd(7), and one Nd(8) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Sr(2), one Sr(3), one Nd(1), one Nd(5), and one Nd(8) atom. In the fourteenth O site, O(14) is bonded in a distorted see-saw-like geometry to one Sr(1), one Nd(1), one Nd(2), and one Nd(7) atom. In the fifteenth O site, O(15) is bonded in a 5-coordinate geometry to one Sr(3), one Sr(5), one Sr(6), one Nd(1), and one Nd(7) atom. In the sixteenth O site, O(16) is bonded to one Sr(5), one Nd(1), one Nd(2), and one Nd(5) atom to form OSrNd3 tetrahedra that share corners with two equivalent O(11)Sr3Nd2 square pyramids,  a cornercorner with one O(7)SrNd3 trigonal pyramid, and  an edgeedge with one O(18)Sr2Nd2 trigonal pyramid. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Sr(4), one Sr(5), one Sr(6), one Nd(3), one Nd(7), and one Nd(8) atom. In the eighteenth O site, O(18) is bonded to one Sr(5), one Sr(6), one Nd(2), and one Nd(7) atom to form OSr2Nd2 trigonal pyramids that share  a cornercorner with one O(4)Sr3Nd2 square pyramid, corners with two equivalent O(11)Sr3Nd2 square pyramids, and  an edgeedge with one O(16)SrNd3 tetrahedra. is represented by the CIF card [CIF]
data_Sr3Nd4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.668
_cell_length_b   7.111
_cell_length_c   10.056
_cell_angle_alpha   99.701
_cell_angle_beta   96.860
_cell_angle_gamma   107.928
_symmetry_Int_Tables_number   1
_cell_volume   571.507
_cell_formula_units_Z   2
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  0.264  0.743  0.021  1.0
  Sr  Sr1  1  0.267  0.343  0.611  1.0
  Sr  Sr2  1  0.408  0.358  0.934  1.0
  Sr  Sr3  1  0.875  0.008  0.565  1.0
  Sr  Sr4  1  0.638  0.085  0.120  1.0
  Sr  Sr5  1  0.974  0.407  0.332  1.0
  Nd  Nd6  1  0.848  0.436  0.926  1.0
  Nd  Nd7  1  0.024  0.047  0.966  1.0
  Nd  Nd8  1  0.455  0.898  0.398  1.0
  Nd  Nd9  1  0.418  0.409  0.290  1.0
  Nd  Nd10  1  0.612  0.792  0.749  1.0
  Nd  Nd11  1  0.131  0.761  0.648  1.0
  Nd  Nd12  1  0.841  0.789  0.233  1.0
  Nd  Nd13  1  0.697  0.378  0.569  1.0
  O  O14  1  0.896  0.766  0.743  1.0
  O  O15  1  0.012  0.800  0.429  1.0
  O  O16  1  0.270  0.566  0.418  1.0
  O  O17  1  0.980  0.393  0.589  1.0
  O  O18  1  0.343  0.681  0.787  1.0
  O  O19  1  0.107  0.391  0.974  1.0
  O  O20  1  0.605  0.012  0.612  1.0
  O  O21  1  0.494  0.712  0.175  1.0
  O  O22  1  0.412  0.204  0.444  1.0
  O  O23  1  0.198  0.094  0.753  1.0
  O  O24  1  0.351  0.131  0.092  1.0
  O  O25  1  0.643  0.620  0.457  1.0
  O  O26  1  0.603  0.451  0.776  1.0
  O  O27  1  0.994  0.749  0.057  1.0
  O  O28  1  0.732  0.440  0.121  1.0
  O  O29  1  0.758  0.071  0.910  1.0
  O  O30  1  0.713  0.112  0.370  1.0
  O  O31  1  0.937  0.099  0.177  1.0
[/CIF]
.