The compound described by NaCa2Mg5AlSi7(O11F)2 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. Na(1) is bonded in a distorted linear geometry to one O(17) and one O(18) atom. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(14), one O(15), one O(2), one O(20), one O(21), one O(3), one O(5), and one O(8) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(1), one O(13), one O(16), one O(19), one O(22), one O(4), one O(6), and one O(7) atom. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(12), one O(5), one O(8), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(2)O4F2 octahedra, edges with two equivalent Mg(3)O4F2 octahedra, and edges with two equivalent Mg(4)O6 octahedra. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(6), one O(7), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, edges with two equivalent Mg(3)O4F2 octahedra, and edges with two equivalent Mg(5)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(10), one O(11), one O(12), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(12), one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, and edges with two equivalent Mg(1)O4F2 octahedra. In the fifth Mg site, Mg(5) is bonded to one O(1), one O(10), one O(11), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. Al(1) is bonded to one O(13), one O(17), one O(19), and one O(9) atom to form AlO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(5)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 62°. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(13), one O(19), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-58°. In the second Si site, Si(2) is bonded to one O(14), one O(2), one O(20), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-57°. In the third Si site, Si(3) is bonded to one O(15), one O(21), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the fourth Si site, Si(4) is bonded to one O(16), one O(22), one O(4), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-56°. In the fifth Si site, Si(5) is bonded to one O(10), one O(14), one O(17), and one O(20) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 58-60°. In the sixth Si site, Si(6) is bonded to one O(11), one O(15), one O(18), and one O(21) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Si(7)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. In the seventh Si site, Si(7) is bonded to one O(12), one O(16), one O(18), and one O(22) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 56-60°. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(5), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(4), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(4), and one Si(3) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(5), and one Si(4) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mg(1), one Mg(4), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Mg(2), one Mg(5), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Mg(2), one Mg(5), and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mg(1), one Mg(4), and one Si(4) atom. In the ninth O site, O(9) is bonded to one Mg(1), one Mg(3), one Mg(4), and one Al(1) atom to form corner-sharing OMg3Al tetrahedra. In the tenth O site, O(10) is bonded to one Mg(2), one Mg(3), one Mg(5), and one Si(5) atom to form distorted OMg3Si trigonal pyramids that share  a cornercorner with one O(9)Mg3Al tetrahedra,  a cornercorner with one O(11)Mg3Si trigonal pyramid, and  an edgeedge with one O(11)Mg3Si trigonal pyramid. In the eleventh O site, O(11) is bonded to one Mg(2), one Mg(3), one Mg(5), and one Si(6) atom to form distorted OMg3Si trigonal pyramids that share  a cornercorner with one O(9)Mg3Al tetrahedra,  a cornercorner with one O(10)Mg3Si trigonal pyramid, and  an edgeedge with one O(10)Mg3Si trigonal pyramid. In the twelfth O site, O(12) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a 2-coordinate geometry to one Ca(2), one Al(1), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(5) atom. In the fifteenth O site, O(15) is bonded in a 2-coordinate geometry to one Ca(1), one Si(3), and one Si(6) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 150 degrees geometry to one Ca(2), one Si(4), and one Si(7) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Al(1), and one Si(5) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Si(6), and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a 2-coordinate geometry to one Ca(2), one Al(1), and one Si(1) atom. In the twentieth O site, O(20) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(5) atom. In the twenty-first O site, O(21) is bonded in a 2-coordinate geometry to one Ca(1), one Si(3), and one Si(6) atom. In the twenty-second O site, O(22) is bonded in a 2-coordinate geometry to one Ca(2), one Si(4), and one Si(7) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Mg(2), and one Mg(3) atom. is represented by the CIF card [CIF]
data_NaCa2Mg5AlSi7(O11F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.333
_cell_length_b   9.981
_cell_length_c   10.369
_cell_angle_alpha   61.357
_cell_angle_beta   82.877
_cell_angle_gamma   75.188
_symmetry_Int_Tables_number   1
_cell_volume   468.280
_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
  Na  Na0  1  0.004  0.496  0.993  1.0
  Ca  Ca1  1  0.498  0.276  0.449  1.0
  Ca  Ca2  1  0.510  0.708  0.562  1.0
  Mg  Mg3  1  0.501  0.093  0.821  1.0
  Mg  Mg4  1  0.500  0.912  0.177  1.0
  Mg  Mg5  1  0.996  0.002  0.998  1.0
  Mg  Mg6  1  0.997  0.179  0.649  1.0
  Mg  Mg7  1  0.001  0.822  0.356  1.0
  Al  Al8  1  0.699  0.365  0.831  1.0
  Si  Si9  1  0.189  0.466  0.654  1.0
  Si  Si10  1  0.196  0.113  0.346  1.0
  Si  Si11  1  0.804  0.542  0.340  1.0
  Si  Si12  1  0.805  0.882  0.658  1.0
  Si  Si13  1  0.704  0.195  0.170  1.0
  Si  Si14  1  0.297  0.639  0.167  1.0
  Si  Si15  1  0.300  0.805  0.832  1.0
  O  O16  1  0.219  0.613  0.495  1.0
  O  O17  1  0.208  0.117  0.498  1.0
  O  O18  1  0.793  0.387  0.491  1.0
  O  O19  1  0.792  0.878  0.507  1.0
  O  O20  1  0.273  0.294  0.656  1.0
  O  O21  1  0.276  0.946  0.343  1.0
  O  O22  1  0.726  0.711  0.340  1.0
  O  O23  1  0.723  0.052  0.656  1.0
  O  O24  1  0.787  0.186  0.829  1.0
  O  O25  1  0.781  0.026  0.173  1.0
  O  O26  1  0.217  0.806  0.168  1.0
  O  O27  1  0.227  0.973  0.831  1.0
  O  O28  1  0.893  0.497  0.718  1.0
  O  O29  1  0.898  0.207  0.276  1.0
  O  O30  1  0.099  0.522  0.263  1.0
  O  O31  1  0.099  0.788  0.735  1.0
  O  O32  1  0.722  0.342  0.010  1.0
  O  O33  1  0.285  0.660  1.000  1.0
  O  O34  1  0.385  0.471  0.764  1.0
  O  O35  1  0.405  0.225  0.236  1.0
  O  O36  1  0.593  0.542  0.230  1.0
  O  O37  1  0.596  0.771  0.769  1.0
  F  F38  1  0.288  0.100  0.002  1.0
  F  F39  1  0.713  0.891  0.005  1.0
[/CIF]
.
The compound described by NaCa2Mg5AlSi7(O11F)2 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. Na(1) is bonded in a distorted linear geometry to one O(17) and one O(18) atom. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(14), one O(15), one O(2), one O(20), one O(21), one O(3), one O(5), and one O(8) atom. In the second Ca site, Ca(2) is bonded in a 8-coordinate geometry to one O(1), one O(13), one O(16), one O(19), one O(22), one O(4), one O(6), and one O(7) atom. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(12), one O(5), one O(8), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(2)O4F2 octahedra, edges with two equivalent Mg(3)O4F2 octahedra, and edges with two equivalent Mg(4)O6 octahedra. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(6), one O(7), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(1)O4F2 octahedra, edges with two equivalent Mg(3)O4F2 octahedra, and edges with two equivalent Mg(5)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(10), one O(11), one O(12), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(12), one O(2), one O(3), one O(5), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Al(1)O4 tetrahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(7)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, and edges with two equivalent Mg(1)O4F2 octahedra. In the fifth Mg site, Mg(5) is bonded to one O(1), one O(10), one O(11), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra,  a cornercorner with one Si(4)O4 tetrahedra,  a cornercorner with one Si(5)O4 tetrahedra,  a cornercorner with one Si(6)O4 tetrahedra,  an edgeedge with one Mg(3)O4F2 octahedra, and edges with two equivalent Mg(2)O4F2 octahedra. Al(1) is bonded to one O(13), one O(17), one O(19), and one O(9) atom to form AlO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(5)O4 tetrahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 62°. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(13), one O(19), and one O(5) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-58°. In the second Si site, Si(2) is bonded to one O(14), one O(2), one O(20), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-57°. In the third Si site, Si(3) is bonded to one O(15), one O(21), one O(3), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(6)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-57°. In the fourth Si site, Si(4) is bonded to one O(16), one O(22), one O(4), and one O(8) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, and corners with two equivalent Si(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-56°. In the fifth Si site, Si(5) is bonded to one O(10), one O(14), one O(17), and one O(20) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, and corners with two equivalent Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 58-60°. In the sixth Si site, Si(6) is bonded to one O(11), one O(15), one O(18), and one O(21) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(2)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(5)O6 octahedra,  a cornercorner with one Si(7)O4 tetrahedra, and corners with two equivalent Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-61°. In the seventh Si site, Si(7) is bonded to one O(12), one O(16), one O(18), and one O(22) atom to form SiO4 tetrahedra that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Mg(3)O4F2 octahedra,  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Si(6)O4 tetrahedra, and corners with two equivalent Si(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 56-60°. There are twenty-two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(5), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(4), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ca(1), one Mg(4), and one Si(3) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Ca(2), one Mg(5), and one Si(4) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mg(1), one Mg(4), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Mg(2), one Mg(5), and one Si(2) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Ca(2), one Mg(2), one Mg(5), and one Si(3) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mg(1), one Mg(4), and one Si(4) atom. In the ninth O site, O(9) is bonded to one Mg(1), one Mg(3), one Mg(4), and one Al(1) atom to form corner-sharing OMg3Al tetrahedra. In the tenth O site, O(10) is bonded to one Mg(2), one Mg(3), one Mg(5), and one Si(5) atom to form distorted OMg3Si trigonal pyramids that share  a cornercorner with one O(9)Mg3Al tetrahedra,  a cornercorner with one O(11)Mg3Si trigonal pyramid, and  an edgeedge with one O(11)Mg3Si trigonal pyramid. In the eleventh O site, O(11) is bonded to one Mg(2), one Mg(3), one Mg(5), and one Si(6) atom to form distorted OMg3Si trigonal pyramids that share  a cornercorner with one O(9)Mg3Al tetrahedra,  a cornercorner with one O(10)Mg3Si trigonal pyramid, and  an edgeedge with one O(10)Mg3Si trigonal pyramid. In the twelfth O site, O(12) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Mg(3), one Mg(4), and one Si(7) atom. In the thirteenth O site, O(13) is bonded in a 2-coordinate geometry to one Ca(2), one Al(1), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(5) atom. In the fifteenth O site, O(15) is bonded in a 2-coordinate geometry to one Ca(1), one Si(3), and one Si(6) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 150 degrees geometry to one Ca(2), one Si(4), and one Si(7) atom. In the seventeenth O site, O(17) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Al(1), and one Si(5) atom. In the eighteenth O site, O(18) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Si(6), and one Si(7) atom. In the nineteenth O site, O(19) is bonded in a 2-coordinate geometry to one Ca(2), one Al(1), and one Si(1) atom. In the twentieth O site, O(20) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(5) atom. In the twenty-first O site, O(21) is bonded in a 2-coordinate geometry to one Ca(1), one Si(3), and one Si(6) atom. In the twenty-second O site, O(22) is bonded in a 2-coordinate geometry to one Ca(2), one Si(4), and one Si(7) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Mg(2), and one Mg(3) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Mg(2), and one Mg(3) atom. is represented by the CIF card [CIF]
data_NaCa2Mg5AlSi7(O11F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.333
_cell_length_b   9.981
_cell_length_c   10.369
_cell_angle_alpha   61.357
_cell_angle_beta   82.877
_cell_angle_gamma   75.188
_symmetry_Int_Tables_number   1
_cell_volume   468.280
_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
  Na  Na0  1  0.004  0.496  0.993  1.0
  Ca  Ca1  1  0.498  0.276  0.449  1.0
  Ca  Ca2  1  0.510  0.708  0.562  1.0
  Mg  Mg3  1  0.501  0.093  0.821  1.0
  Mg  Mg4  1  0.500  0.912  0.177  1.0
  Mg  Mg5  1  0.996  0.002  0.998  1.0
  Mg  Mg6  1  0.997  0.179  0.649  1.0
  Mg  Mg7  1  0.001  0.822  0.356  1.0
  Al  Al8  1  0.699  0.365  0.831  1.0
  Si  Si9  1  0.189  0.466  0.654  1.0
  Si  Si10  1  0.196  0.113  0.346  1.0
  Si  Si11  1  0.804  0.542  0.340  1.0
  Si  Si12  1  0.805  0.882  0.658  1.0
  Si  Si13  1  0.704  0.195  0.170  1.0
  Si  Si14  1  0.297  0.639  0.167  1.0
  Si  Si15  1  0.300  0.805  0.832  1.0
  O  O16  1  0.219  0.613  0.495  1.0
  O  O17  1  0.208  0.117  0.498  1.0
  O  O18  1  0.793  0.387  0.491  1.0
  O  O19  1  0.792  0.878  0.507  1.0
  O  O20  1  0.273  0.294  0.656  1.0
  O  O21  1  0.276  0.946  0.343  1.0
  O  O22  1  0.726  0.711  0.340  1.0
  O  O23  1  0.723  0.052  0.656  1.0
  O  O24  1  0.787  0.186  0.829  1.0
  O  O25  1  0.781  0.026  0.173  1.0
  O  O26  1  0.217  0.806  0.168  1.0
  O  O27  1  0.227  0.973  0.831  1.0
  O  O28  1  0.893  0.497  0.718  1.0
  O  O29  1  0.898  0.207  0.276  1.0
  O  O30  1  0.099  0.522  0.263  1.0
  O  O31  1  0.099  0.788  0.735  1.0
  O  O32  1  0.722  0.342  0.010  1.0
  O  O33  1  0.285  0.660  1.000  1.0
  O  O34  1  0.385  0.471  0.764  1.0
  O  O35  1  0.405  0.225  0.236  1.0
  O  O36  1  0.593  0.542  0.230  1.0
  O  O37  1  0.596  0.771  0.769  1.0
  F  F38  1  0.288  0.100  0.002  1.0
  F  F39  1  0.713  0.891  0.005  1.0
[/CIF]
.