data_global
_chemical_name_mineral 'Nenadkevichite'
loop_
_publ_author_name
'Rastsvetaeva R K'
'Tamazyan R A'
'Pushcharovsky D Y'
'Nadezhina T N'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 6 
_journal_year 1994
_journal_page_first 503
_journal_page_last 509
_publ_section_title
;
 Crystal structure and microtwinning of K-rich nenadkevichite
 Note: Wat4 y-coordinate changed to reproduce reported bond lengths
;
_database_code_amcsd 0006548
_chemical_formula_sum 'K2.98 Na1.22 (Nb2.2 Ti1.8) Si8 O31.15 H6.3'
_cell_length_a 14.692
_cell_length_b 14.164
_cell_length_c 7.859
_cell_angle_alpha 90
_cell_angle_beta 117.87
_cell_angle_gamma 90
_cell_volume 1445.745
_exptl_crystal_density_diffrn      2.675
_symmetry_space_group_name_H-M 'C 1 m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
K1   0.50010   0.81940   0.98300   0.76000   0.04306
K2   0.43200   0.00000   0.70500   0.53000   0.08612
K3   0.91000   0.00000   0.64800   0.44000   0.03800
K4   0.08100   0.00000   0.28800   0.49000   0.04686
Na1   0.00900   0.00000   0.46800   0.58000   0.02406
Na2   0.79600   0.00000   0.52900   0.39000   0.11145
Na3   0.00600   0.00000   0.10900   0.25000   0.17605
NbM1   0.00000   0.76910   0.50000   0.60000   0.00405
TiM1   0.00000   0.76910   0.50000   0.40000   0.00405
NbM2   0.74340   0.74800   0.46440   0.50000   0.00671
TiM2   0.74340   0.74800   0.46440   0.50000   0.00671
Si1   0.21700   0.89200   0.78000   1.00000   0.01900
Si2   0.69180   0.89160   0.73600   1.00000   0.02533
Si3   0.80550   0.89010   0.18600   1.00000   0.01140
Si4   0.32870   0.89140   0.23000   1.00000   0.01267
O1   0.91100   0.76600   0.58600   1.00000   0.04053
O2   0.92500   0.87300   0.30800   1.00000   0.02280
O3   0.26800   0.86700   0.34100   1.00000   0.02153
O4   0.27400   0.82300   0.70200   1.00000   0.04179
O5   0.42900   0.82560   0.28500   1.00000   0.01773
O6   0.37500   0.00000   0.28000   1.00000   0.03673
O7   0.25120   0.87900   0.00300   1.00000   0.02533
O8   0.22700   0.00000   0.73000   1.00000   0.02280
O9   0.10400   0.76820   0.37200   1.00000   0.00760
O10   0.09200   0.87000   0.66500   1.00000   0.02913
O11   0.74700   0.86520   0.60100   1.00000   0.02660
O12   0.73200   0.82440   0.24500   1.00000   0.01140
O13   0.59100   0.82600   0.67200   1.00000   0.02913
O14   0.65600   0.00000   0.71100   1.00000   0.01900
O15   0.77100   0.87200   0.95600   1.00000   0.03673
O16   0.77700   0.00000   0.20400   1.00000   0.02153
Wat1   0.03000   0.88000   0.98200   0.56000   0.03420
Wat2   0.56400   0.00000   0.21200   0.61000   0.05319
Wat3   0.29900   0.00000   0.51300   0.32000   0.03293
Wat4   0.03600   0.82700   0.02500   0.37000   0.15831
Wat5   0.51400   0.00000   0.89100   0.36000   0.07726