The material structure described by K2Ca3Si3O10 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(3), two equivalent O(5), and three equivalent O(2) atoms. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ca(1)O6 octahedra and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 12-44°. In the second Si site, Si(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form corner-sharing SiO4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(1), one Ca(1), one Ca(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to three equivalent K(1), one Si(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent K(1), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ca(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Ca3Si3O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.499
_cell_length_b   7.499
_cell_length_c   9.929
_cell_angle_alpha   71.042
_cell_angle_beta   71.042
_cell_angle_gamma   91.682
_symmetry_Int_Tables_number   1
_cell_volume   493.680
_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
  K  K0  1  0.231  0.474  0.511  1.0
  K  K1  1  0.526  0.769  0.989  1.0
  K  K2  1  0.769  0.526  0.489  1.0
  K  K3  1  0.474  0.231  0.011  1.0
  Ca  Ca4  1  0.370  0.630  0.750  1.0
  Ca  Ca5  1  0.630  0.370  0.250  1.0
  Ca  Ca6  1  0.222  0.984  0.522  1.0
  Ca  Ca7  1  0.016  0.778  0.978  1.0
  Ca  Ca8  1  0.778  0.016  0.478  1.0
  Ca  Ca9  1  0.984  0.222  0.022  1.0
  Si  Si10  1  0.576  0.852  0.292  1.0
  Si  Si11  1  0.148  0.424  0.208  1.0
  Si  Si12  1  0.424  0.148  0.708  1.0
  Si  Si13  1  0.852  0.576  0.792  1.0
  Si  Si14  1  0.159  0.841  0.250  1.0
  Si  Si15  1  0.841  0.159  0.750  1.0
  O  O16  1  0.690  0.680  0.733  1.0
  O  O17  1  0.320  0.310  0.767  1.0
  O  O18  1  0.310  0.320  0.267  1.0
  O  O19  1  0.680  0.690  0.233  1.0
  O  O20  1  0.120  0.615  0.263  1.0
  O  O21  1  0.385  0.880  0.237  1.0
  O  O22  1  0.880  0.385  0.737  1.0
  O  O23  1  0.615  0.120  0.763  1.0
  O  O24  1  0.494  0.787  0.481  1.0
  O  O25  1  0.213  0.506  0.019  1.0
  O  O26  1  0.506  0.213  0.519  1.0
  O  O27  1  0.787  0.494  0.981  1.0
  O  O28  1  0.066  0.696  0.727  1.0
  O  O29  1  0.304  0.934  0.773  1.0
  O  O30  1  0.934  0.304  0.273  1.0
  O  O31  1  0.696  0.066  0.227  1.0
  O  O32  1  0.139  0.972  0.092  1.0
  O  O33  1  0.028  0.861  0.408  1.0
  O  O34  1  0.861  0.028  0.908  1.0
  O  O35  1  0.972  0.139  0.592  1.0
[/CIF]
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The material structure described by K2Ca3Si3O10 crystallizes in the monoclinic C2/c space group. K(1) is bonded in a 10-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(3), two equivalent O(5), and three equivalent O(2) atoms. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form CaO6 octahedra that share corners with six equivalent Si(1)O4 tetrahedra. In the second Ca site, Ca(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ca(1)O6 octahedra and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 12-44°. In the second Si site, Si(2) is bonded to two equivalent O(2) and two equivalent O(5) atoms to form corner-sharing SiO4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(1), one Ca(1), one Ca(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to three equivalent K(1), one Si(1), and one Si(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent K(1), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one K(1), one Ca(1), two equivalent Ca(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Ca(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Ca3Si3O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.499
_cell_length_b   7.499
_cell_length_c   9.929
_cell_angle_alpha   71.042
_cell_angle_beta   71.042
_cell_angle_gamma   91.682
_symmetry_Int_Tables_number   1
_cell_volume   493.680
_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
  K  K0  1  0.231  0.474  0.511  1.0
  K  K1  1  0.526  0.769  0.989  1.0
  K  K2  1  0.769  0.526  0.489  1.0
  K  K3  1  0.474  0.231  0.011  1.0
  Ca  Ca4  1  0.370  0.630  0.750  1.0
  Ca  Ca5  1  0.630  0.370  0.250  1.0
  Ca  Ca6  1  0.222  0.984  0.522  1.0
  Ca  Ca7  1  0.016  0.778  0.978  1.0
  Ca  Ca8  1  0.778  0.016  0.478  1.0
  Ca  Ca9  1  0.984  0.222  0.022  1.0
  Si  Si10  1  0.576  0.852  0.292  1.0
  Si  Si11  1  0.148  0.424  0.208  1.0
  Si  Si12  1  0.424  0.148  0.708  1.0
  Si  Si13  1  0.852  0.576  0.792  1.0
  Si  Si14  1  0.159  0.841  0.250  1.0
  Si  Si15  1  0.841  0.159  0.750  1.0
  O  O16  1  0.690  0.680  0.733  1.0
  O  O17  1  0.320  0.310  0.767  1.0
  O  O18  1  0.310  0.320  0.267  1.0
  O  O19  1  0.680  0.690  0.233  1.0
  O  O20  1  0.120  0.615  0.263  1.0
  O  O21  1  0.385  0.880  0.237  1.0
  O  O22  1  0.880  0.385  0.737  1.0
  O  O23  1  0.615  0.120  0.763  1.0
  O  O24  1  0.494  0.787  0.481  1.0
  O  O25  1  0.213  0.506  0.019  1.0
  O  O26  1  0.506  0.213  0.519  1.0
  O  O27  1  0.787  0.494  0.981  1.0
  O  O28  1  0.066  0.696  0.727  1.0
  O  O29  1  0.304  0.934  0.773  1.0
  O  O30  1  0.934  0.304  0.273  1.0
  O  O31  1  0.696  0.066  0.227  1.0
  O  O32  1  0.139  0.972  0.092  1.0
  O  O33  1  0.028  0.861  0.408  1.0
  O  O34  1  0.861  0.028  0.908  1.0
  O  O35  1  0.972  0.139  0.592  1.0
[/CIF]
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