The compound described by K2B4GeO11 crystallizes in the monoclinic Cc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(1), one O(11), one O(2), one O(4), one O(5), one O(6), one O(7), one O(9), and two equivalent O(10) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(8), and one O(9) atom. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(8) atom. In the second B site, B(2) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form BO4 tetrahedra that share  a cornercorner with one B(4)O4 tetrahedra and  a cornercorner with one Ge(1)O4 tetrahedra. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. In the fourth B site, B(4) is bonded to one O(1), one O(7), one O(8), and one O(9) atom to form BO4 tetrahedra that share  a cornercorner with one B(2)O4 tetrahedra and  a cornercorner with one Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share  a cornercorner with one B(2)O4 tetrahedra and  a cornercorner with one B(4)O4 tetrahedra. There are eleven inequivalent O sites. In the first O site, O(3) is bonded in a 2-coordinate geometry to one K(2), one B(1), and one Ge(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(2), and one Ge(1) atom. In the third O site, O(5) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the fourth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(3), and one Ge(1) atom. In the fifth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(3), and one B(4) atom. In the sixth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(2), one B(1), and one B(4) atom. In the seventh O site, O(9) is bonded in a distorted water-like geometry to one K(1), one K(2), one B(2), and one B(4) atom. In the eighth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to one K(2), two equivalent K(1), and one O(11) atom. In the ninth O site, O(11) is bonded in a 2-coordinate geometry to one K(1) and one O(10) atom. In the tenth O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(4), and one Ge(1) atom. In the eleventh O site, O(2) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(1), and one B(2) atom. is represented by the CIF file [CIF]
data_K2GeB4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.013
_cell_length_b   7.013
_cell_length_c   12.030
_cell_angle_alpha   89.287
_cell_angle_beta   89.287
_cell_angle_gamma   121.573
_symmetry_Int_Tables_number   1
_cell_volume   503.898
_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  0.440  0.527  0.891  1.0
  K  K1  1  0.527  0.440  0.391  1.0
  K  K2  1  0.308  0.813  0.619  1.0
  K  K3  1  0.813  0.308  0.119  1.0
  Ge  Ge4  1  0.823  0.239  0.795  1.0
  Ge  Ge5  1  0.239  0.823  0.295  1.0
  B  B6  1  0.922  0.298  0.558  1.0
  B  B7  1  0.298  0.922  0.058  1.0
  B  B8  1  0.034  0.362  0.360  1.0
  B  B9  1  0.362  0.034  0.860  1.0
  B  B10  1  0.930  0.965  0.346  1.0
  B  B11  1  0.965  0.930  0.846  1.0
  B  B12  1  0.662  0.066  0.409  1.0
  B  B13  1  0.066  0.662  0.909  1.0
  O  O14  1  0.419  0.981  0.403  1.0
  O  O15  1  0.981  0.419  0.903  1.0
  O  O16  1  0.087  0.430  0.480  1.0
  O  O17  1  0.430  0.087  0.980  1.0
  O  O18  1  0.976  0.366  0.668  1.0
  O  O19  1  0.366  0.976  0.168  1.0
  O  O20  1  0.180  0.549  0.283  1.0
  O  O21  1  0.549  0.180  0.783  1.0
  O  O22  1  0.094  0.187  0.338  1.0
  O  O23  1  0.187  0.094  0.838  1.0
  O  O24  1  0.975  0.797  0.323  1.0
  O  O25  1  0.797  0.975  0.823  1.0
  O  O26  1  0.712  0.891  0.377  1.0
  O  O27  1  0.891  0.712  0.877  1.0
  O  O28  1  0.718  0.118  0.531  1.0
  O  O29  1  0.118  0.718  0.031  1.0
  O  O30  1  0.797  0.269  0.342  1.0
  O  O31  1  0.269  0.797  0.842  1.0
  O  O32  1  0.523  0.554  0.137  1.0
  O  O33  1  0.554  0.523  0.637  1.0
  O  O34  1  0.743  0.677  0.606  1.0
  O  O35  1  0.677  0.743  0.106  1.0
[/CIF]
.
The compound described by K2B4GeO11 crystallizes in the monoclinic Cc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(1), one O(11), one O(2), one O(4), one O(5), one O(6), one O(7), one O(9), and two equivalent O(10) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(4), one O(8), and one O(9) atom. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(2), one O(3), and one O(8) atom. In the second B site, B(2) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form BO4 tetrahedra that share  a cornercorner with one B(4)O4 tetrahedra and  a cornercorner with one Ge(1)O4 tetrahedra. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(5), one O(6), and one O(7) atom. In the fourth B site, B(4) is bonded to one O(1), one O(7), one O(8), and one O(9) atom to form BO4 tetrahedra that share  a cornercorner with one B(2)O4 tetrahedra and  a cornercorner with one Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share  a cornercorner with one B(2)O4 tetrahedra and  a cornercorner with one B(4)O4 tetrahedra. There are eleven inequivalent O sites. In the first O site, O(3) is bonded in a 2-coordinate geometry to one K(2), one B(1), and one Ge(1) atom. In the second O site, O(4) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(2), and one Ge(1) atom. In the third O site, O(5) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(2), and one B(3) atom. In the fourth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(3), and one Ge(1) atom. In the fifth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one K(1), one B(3), and one B(4) atom. In the sixth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(2), one B(1), and one B(4) atom. In the seventh O site, O(9) is bonded in a distorted water-like geometry to one K(1), one K(2), one B(2), and one B(4) atom. In the eighth O site, O(10) is bonded in a distorted rectangular see-saw-like geometry to one K(2), two equivalent K(1), and one O(11) atom. In the ninth O site, O(11) is bonded in a 2-coordinate geometry to one K(1) and one O(10) atom. In the tenth O site, O(1) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(4), and one Ge(1) atom. In the eleventh O site, O(2) is bonded in a distorted bent 120 degrees geometry to one K(1), one K(2), one B(1), and one B(2) atom. is represented by the CIF file [CIF]
data_K2GeB4O11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.013
_cell_length_b   7.013
_cell_length_c   12.030
_cell_angle_alpha   89.287
_cell_angle_beta   89.287
_cell_angle_gamma   121.573
_symmetry_Int_Tables_number   1
_cell_volume   503.898
_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  0.440  0.527  0.891  1.0
  K  K1  1  0.527  0.440  0.391  1.0
  K  K2  1  0.308  0.813  0.619  1.0
  K  K3  1  0.813  0.308  0.119  1.0
  Ge  Ge4  1  0.823  0.239  0.795  1.0
  Ge  Ge5  1  0.239  0.823  0.295  1.0
  B  B6  1  0.922  0.298  0.558  1.0
  B  B7  1  0.298  0.922  0.058  1.0
  B  B8  1  0.034  0.362  0.360  1.0
  B  B9  1  0.362  0.034  0.860  1.0
  B  B10  1  0.930  0.965  0.346  1.0
  B  B11  1  0.965  0.930  0.846  1.0
  B  B12  1  0.662  0.066  0.409  1.0
  B  B13  1  0.066  0.662  0.909  1.0
  O  O14  1  0.419  0.981  0.403  1.0
  O  O15  1  0.981  0.419  0.903  1.0
  O  O16  1  0.087  0.430  0.480  1.0
  O  O17  1  0.430  0.087  0.980  1.0
  O  O18  1  0.976  0.366  0.668  1.0
  O  O19  1  0.366  0.976  0.168  1.0
  O  O20  1  0.180  0.549  0.283  1.0
  O  O21  1  0.549  0.180  0.783  1.0
  O  O22  1  0.094  0.187  0.338  1.0
  O  O23  1  0.187  0.094  0.838  1.0
  O  O24  1  0.975  0.797  0.323  1.0
  O  O25  1  0.797  0.975  0.823  1.0
  O  O26  1  0.712  0.891  0.377  1.0
  O  O27  1  0.891  0.712  0.877  1.0
  O  O28  1  0.718  0.118  0.531  1.0
  O  O29  1  0.118  0.718  0.031  1.0
  O  O30  1  0.797  0.269  0.342  1.0
  O  O31  1  0.269  0.797  0.842  1.0
  O  O32  1  0.523  0.554  0.137  1.0
  O  O33  1  0.554  0.523  0.637  1.0
  O  O34  1  0.743  0.677  0.606  1.0
  O  O35  1  0.677  0.743  0.106  1.0
[/CIF]
.