data_Mn2Si2Pb2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.33
_cell_length_b   6.33
_cell_length_c   11.34
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   108.27
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2Si2Pb2O9
_chemical_formula_sum   'Mn4 Si4 Pb4 O18'
_cell_volume   431.2
_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
  Mn  Mn0  1  0.06  0.0  0.67  1.0
  Mn  Mn1  1  0.71  0.9  0.84  1.0
  Mn  Mn2  1  0.71  0.1  0.51  1.0
  Mn  Mn3  1  0.35  0.0  0.0  1.0
  Si  Si4  1  0.2  0.02  0.1  1.0
  Si  Si5  1  0.2  0.98  0.25  1.0
  Si  Si6  1  0.22  0.02  0.57  1.0
  Si  Si7  1  0.22  0.98  0.77  1.0
  Pb  Pb8  1  0.5  0.64  0.32  1.0
  Pb  Pb9  1  0.92  0.64  0.35  1.0
  Pb  Pb10  1  0.92  0.36  0.99  1.0
  Pb  Pb11  1  0.5  0.36  0.02  1.0
  O  O12  1  0.71  0.37  0.84  1.0
  O  O13  1  0.59  0.73  0.98  1.0
  O  O14  1  0.16  0.36  0.61  1.0
  O  O15  1  0.17  0.47  0.29  1.0
  O  O16  1  0.59  0.27  0.36  1.0
  O  O17  1  0.56  0.35  0.54  1.0
  O  O18  1  0.83  0.27  0.65  1.0
  O  O19  1  0.56  0.65  0.8  1.0
  O  O20  1  0.71  0.63  0.51  1.0
  O  O21  1  0.83  0.73  0.69  1.0
  O  O22  1  0.25  0.53  0.96  1.0
  O  O23  1  0.25  0.47  0.38  1.0
  O  O24  1  0.25  0.36  0.4  1.0
  O  O25  1  0.86  0.65  0.21  1.0
  O  O26  1  0.17  0.53  0.05  1.0
  O  O27  1  0.25  0.64  0.94  1.0
  O  O28  1  0.16  0.64  0.73  1.0
  O  O29  1  0.86  0.35  0.13  1.0

data_Mn2Si2Pb2O9
_symmetry_space_group_name_H-M   P1
_cell_length_a   6.33
_cell_length_b   6.33
_cell_length_c   11.34
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   108.27
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2Si2Pb2O9
_chemical_formula_sum   'Mn4 Si4 Pb4 O18'
_cell_volume   431.2
_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
  Mn  Mn0  1  0.06  0.0  0.67  1.0
  Mn  Mn1  1  0.35  0.0  0.0  1.0
  Mn  Mn2  1  0.71  0.1  0.51  1.0
  Mn  Mn3  1  0.71  0.9  0.84  1.0
  Si  Si4  1  0.2  0.02  0.1  1.0
  Si  Si5  1  0.2  0.98  0.25  1.0
  Si  Si6  1  0.22  0.02  0.57  1.0
  Si  Si7  1  0.22  0.98  0.77  1.0
  Pb  Pb8  1  0.5  0.36  0.02  1.0
  Pb  Pb9  1  0.5  0.64  0.32  1.0
  Pb  Pb10  1  0.92  0.36  0.99  1.0
  Pb  Pb11  1  0.92  0.64  0.35  1.0
  O  O12  1  0.16  0.64  0.73  1.0
  O  O13  1  0.16  0.36  0.61  1.0
  O  O14  1  0.17  0.53  0.05  1.0
  O  O15  1  0.17  0.47  0.29  1.0
  O  O16  1  0.25  0.53  0.96  1.0
  O  O17  1  0.25  0.47  0.38  1.0
  O  O18  1  0.25  0.36  0.4  1.0
  O  O19  1  0.25  0.64  0.94  1.0
  O  O20  1  0.56  0.35  0.54  1.0
  O  O21  1  0.56  0.65  0.8  1.0
  O  O22  1  0.59  0.27  0.36  1.0
  O  O23  1  0.59  0.73  0.98  1.0
  O  O24  1  0.71  0.37  0.84  1.0
  O  O25  1  0.71  0.63  0.51  1.0
  O  O26  1  0.83  0.27  0.65  1.0
  O  O27  1  0.83  0.73  0.69  1.0
  O  O28  1  0.86  0.35  0.13  1.0
  O  O29  1  0.86  0.65  0.21  1.0

Mn Mn Mn Mn Si Si Si Si Pb Pb Pb Pb O O O O O O O O O O O O O O O O O O
Mn Mn Mn Mn Si Si Si Si Pb Pb Pb Pb O O O O O O O O O O O O O O O O O O 0 7 o - o 0 6 o o o 0 14 o o o 0 21 - - o 0 28 o - o 1 19 o o o 1 13 o o o 1 21 o o o 2 16 o o o 2 17 o o o 2 18 o o o 3 4 o o o 3 11 o o o 4 5 o - o 4 11 o o o 6 14 o o o 7 28 o o o 8 15 o o o 8 24 o o o 8 23 o o o 8 16 o o o 9 25 o o o 9 16 o o o 9 20 o o o 10 29 o o + 10 26 + o + 10 11 o o + 10 12 o o o 11 22 o o - 11 13 o o - 11 26 o o o 11 29 o o o 11 12 o o - 12 19 o o o 12 18 o o o 12 21 o o o 13 27 o o o 13 22 o o o 13 19 o o o 14 18 - o o 14 28 o o o 14 17 o o o 14 24 o o o 15 23 o o o 16 24 o o o 16 17 o o o 16 20 o o o 17 18 o o o 17 20 o o o 19 21 o o o 19 28 o o o 20 21 o o o 21 28 + o o 22 27 o o o 22 26 o o + 23 24 o o o 27 28 o o o 
Pb2Mn2Si2O9 crystallizes in the triclinic P1 space group. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 5-coordinate geometry to one Si(3), one Si(4), one O(10), one O(3), and one O(7) atom. The Mn(1)-Si(3) bond length is 1.43 Å. The Mn(1)-Si(4) bond length is 1.49 Å. The Mn(1)-O(10) bond length is 1.90 Å. The Mn(1)-O(3) bond length is 2.25 Å. The Mn(1)-O(7) bond length is 2.60 Å. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to one O(10), one O(2), and one O(8) atom. The Mn(2)-O(10) bond length is 2.22 Å. The Mn(2)-O(2) bond length is 1.97 Å. The Mn(2)-O(8) bond length is 1.61 Å. In the third Mn site, Mn(3) is bonded in a 3-coordinate geometry to one O(5), one O(6), and one O(7) atom. The Mn(3)-O(5) bond length is 2.22 Å. The Mn(3)-O(6) bond length is 2.11 Å. The Mn(3)-O(7) bond length is 1.97 Å. In the fourth Mn site, Mn(4) is bonded in a 5-coordinate geometry to one Pb(4), one Si(1), one Si(4), one O(16), and one O(2) atom. The Mn(4)-Pb(4) bond length is 2.20 Å. The Mn(4)-Si(1) bond length is 1.49 Å. The Mn(4)-Si(4) bond length is 2.78 Å. The Mn(4)-O(16) bond length is 2.25 Å. The Mn(4)-O(2) bond length is 2.60 Å. There are four inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 1-coordinate geometry to one O(12), one O(4), one O(5), and one O(9) atom. The Pb(1)-O(12) bond length is 1.76 Å. The Pb(1)-O(4) bond length is 2.08 Å. The Pb(1)-O(5) bond length is 2.59 Å. The Pb(1)-O(9) bond length is 2.48 Å. In the second Pb site, Pb(2) is bonded in a 1-coordinate geometry to one Si(2), one O(14), one O(4), one O(5), and one O(9) atom. The Pb(2)-Si(2) bond length is 2.60 Å. The Pb(2)-O(14) bond length is 1.61 Å. The Pb(2)-O(4) bond length is 2.29 Å. The Pb(2)-O(5) bond length is 2.60 Å. The Pb(2)-O(9) bond length is 2.20 Å. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to one O(1), one O(15), and one O(18) atom. The Pb(3)-O(1) bond length is 2.21 Å. The Pb(3)-O(15) bond length is 1.76 Å. The Pb(3)-O(18) bond length is 1.59 Å. In the fourth Pb site, Pb(4) is bonded in a 5-coordinate geometry to one Mn(4), one O(1), one O(11), one O(18), and one O(2) atom. The Pb(4)-O(1) bond length is 2.47 Å. The Pb(4)-O(11) bond length is 2.29 Å. The Pb(4)-O(18) bond length is 2.62 Å. The Pb(4)-O(2) bond length is 2.26 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted single-bond geometry to one Mn(4) and one Si(2) atom. The Si(1)-Si(2) bond length is 1.72 Å. In the second Si site, Si(2) is bonded in a 3-coordinate geometry to one Pb(2), one Si(1), and one O(14) atom. The Si(2)-O(14) bond length is 2.48 Å. In the third Si site, Si(3) is bonded in a 1-coordinate geometry to one Mn(1) and one O(3) atom. The Si(3)-O(3) bond length is 2.27 Å. In the fourth Si site, Si(4) is bonded in a distorted L-shaped geometry to one Mn(1), one Mn(4), and one O(17) atom. The Si(4)-O(17) bond length is 2.07 Å. There are eighteen inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Pb(3) and one Pb(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Mn(2), one Mn(4), and one Pb(4) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Mn(1) and one Si(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Pb(1), one Pb(2), and one O(12) atom. The O(4)-O(12) bond length is 1.23 Å. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mn(3), one Pb(1), and one Pb(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Mn(3) and one O(9) atom. The O(6)-O(9) bond length is 1.81 Å. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Mn(1) and one Mn(3) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Mn(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Pb(1), one Pb(2), and one O(6) atom. In the tenth O site, O(10) is bonded in a distorted L-shaped geometry to one Mn(1) and one Mn(2) atom. In the eleventh O site, O(11) is bonded in a 1-coordinate geometry to one Pb(4), one O(15), and one O(16) atom. The O(11)-O(15) bond length is 1.23 Å. The O(11)-O(16) bond length is 0.72 Å. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Pb(1), one O(13), and one O(4) atom. The O(12)-O(13) bond length is 0.72 Å. In the thirteenth O site, O(13) is bonded in a single-bond geometry to one O(12) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one Pb(2) and one Si(2) atom. In the fifteenth O site, O(15) is bonded in a distorted L-shaped geometry to one Pb(3) and one O(11) atom. In the sixteenth O site, O(16) is bonded in a distorted bent 150 degrees geometry to one Mn(4) and one O(11) atom. In the seventeenth O site, O(17) is bonded in a single-bond geometry to one Si(4) atom. In the eighteenth O site, O(18) is bonded in a distorted single-bond geometry to one Pb(3) and one Pb(4) atom.