data_global
_chemical_name_mineral 'Trikalsilite'
loop_
_publ_author_name
'Bonaccorsi E'
'Merlino S'
'Pasero M'
_journal_name_full 'Neues Jahrbuch fur Mineralogie, Monatshefte'
_journal_volume 1988 
_journal_year 1988
_journal_page_first 559
_journal_page_last 567
_publ_section_title
;
 Trikalsilite: its structural relationships with nepheline and tetraskalsilite
;
_database_code_amcsd 0014833
_chemical_compound_source 'Near Mt. Nyiragongo, Virunga volcanic field, North Kivu, Zaire'
_chemical_formula_sum 'Na K2 Al3 Si3 O12'
_cell_length_a 15.339
_cell_length_b 15.339
_cell_length_c 8.501
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 120
_cell_volume 1732.187
_exptl_crystal_density_diffrn      2.637
_symmetry_space_group_name_H-M 'P 63'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x-y,x,1/2+z'
  '-y,x-y,z'
  '-x,-y,1/2+z'
  '-x+y,-x,z'
  'y,-x+y,1/2+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
NaM2   0.36890   0.01330   0.75000   0.70000   0.02406
KM2   0.36890   0.01330   0.75000   0.30000   0.02406
KM1   0.00000   0.00000   0.75530   1.00000   0.01773
KM3   0.29220   0.31950   0.74740   0.70000   0.01900
NaM3   0.29220   0.31950   0.74740   0.30000   0.01900
KM4   0.33333   0.66667   0.73710   1.00000   0.03293
KM5   0.66667   0.33333   0.76010   1.00000   0.01140
Al1   0.44530   0.23510   0.55370   1.00000   0.00633
Al2   0.05440   0.21470   0.56380   1.00000   0.01267
Al3   0.41470   0.53540   0.56140   1.00000   0.00887
Si1   0.19470   0.43740   0.43730   1.00000   0.00633
Si2   0.21960   0.15930   0.43610   1.00000   0.01393
Si3   0.56630   0.45720   0.44250   1.00000   0.00887
O1   0.18300   0.43200   0.25300   1.00000   0.06713
O2   0.20100   0.18400   0.25500   1.00000   0.02153
O3   0.56000   0.45300   0.25000   1.00000   0.09499
O4   0.19700   0.54200   0.47200   1.00000   0.02153
O5   0.54600   0.34800   0.49400   1.00000   0.01393
O6   0.10800   0.34300   0.51600   1.00000   0.02153
O7   0.33500   0.22700   0.47900   1.00000   0.03293
O8   0.15400   0.19000   0.55600   1.00000   0.00887
O9   0.17300   0.03700   0.44500   1.00000   0.01520
O10   0.30500   0.44800   0.45800   1.00000   0.01646
O11   0.45800   0.14000   0.47900   1.00000   0.01646
O12   0.49300   0.48700   0.52700   1.00000   0.04179