data_global
_chemical_name_mineral 'Melilite'
loop_
_publ_author_name
'Bindi L'
'Bonazzi P'
'Fitton J G'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 13 
_journal_year 2001
_journal_page_first 121
_journal_page_last 125
_publ_section_title
;
 Crystal chemistry of strontian soda melilite from nephelinite
 lave of Mt. Etinde, Cameroon
 Sample: ET2
;
_database_code_amcsd 0006852
_chemical_compound_source 'nephelinite lava of Mt. Etinde, Cameroon'
_chemical_formula_sum '(Ca.83 Sr.45 Na.72) Mg.2 Fe.29 Mn.03 Zn.01 Al.46 Ti.02 Si1.99 O7'
_cell_length_a 7.764
_cell_length_b 7.764
_cell_length_c 5.095
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 307.125
_exptl_crystal_density_diffrn      3.178
_symmetry_space_group_name_H-M 'P -4 21 m'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2-y,1/2-x,z'
  'y,-x,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,z'
  '1/2+y,1/2+x,z'
  '-y,x,-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
CaX   0.33731   0.16269   0.50936   0.41500   0.02310
SrX   0.33731   0.16269   0.50936   0.22500   0.02310
NaX   0.33731   0.16269   0.50936   0.36000   0.02310
MgT1   0.00000   0.00000   0.00000   0.20000   0.01980
FeT1   0.00000   0.00000   0.00000   0.29000   0.01980
MnT1   0.00000   0.00000   0.00000   0.03000   0.01980
ZnT1   0.00000   0.00000   0.00000   0.01000   0.01980
AlT1   0.00000   0.00000   0.00000   0.45000   0.01980
TiT1   0.00000   0.00000   0.00000   0.02000   0.01980
SiT2   0.14010   0.35990   0.95101   0.99500   0.01890
AlT2   0.14010   0.35990   0.95101   0.00500   0.01890
O1   0.50000   0.00000   0.16428   1.00000   0.03280
O2   0.14225   0.35775   0.25769   1.00000   0.03280
O3   0.08210   0.18041   0.81181   1.00000   0.03380