data_1100091
_chemical_name_systematic          'Magnesium sulfate heptahydrate'
_chemical_name_mineral             'Epsomite'
_chemical_formula_structural       'Mg S O4 (H2 O)7'
_chemical_formula_sum              'H14 Mg O11 S'
_publ_section_title
;
On the Crystal Chemistry of Salt Hydrates. IV. The Refinement of the
Crystal Structure of Mg S O4 (H2 O)7 (Epsomite)
;
_publ_author_name                  'Baur, W H'
_journal_name_full                 'Acta Crystallographica (1,1948-23,1967)'
_journal_volume                    17
_journal_year                      1964
_journal_page_first                1361
_journal_page_last                 1369
_cell_length_a                     11.868(10)
_cell_length_b                     11.996(10)
_cell_length_c                     6.857(7)
_cell_angle_alpha                  90
_cell_angle_beta                   90
_cell_angle_gamma                  90
_cell_volume                       976.2
_cell_formula_units_Z              4
_exptl_crystal_density_meas        1.68
_symmetry_space_group_name_H-M     'P 21 21 21'
_symmetry_Int_Tables_number        19
_symmetry_cell_setting             orthorhombic
loop_
_symmetry_equiv_pos_as_xyz
  'x,y,z'
  '1/2-x,-y,1/2+z'
  '1/2+x,1/2-y,-z'
  '-x,1/2+y,1/2-z'
loop_
_atom_type_symbol
_atom_type_oxidation_number
  Mg2+   2.000
  S6+    6.000
  O2-   -2.000
  H1+    1.000
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_symmetry_multiplicity
_atom_site_Wyckoff_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_attached_hydrogens
_atom_site_calc_flag
  Mg1   Mg2+   4 a 0.4229(1) 0.1063(1) 0.0340(2) 1.  0 d
  S1    S6+    4 a 0.7266(1) 0.1839(1) 0.4905(1) 1.  0 d
  O1    O2-    4 a 0.6853(4) 0.0750(4) 0.4279(7) 1.  0 d
  O2    O2-    4 a 0.8506(3) 0.1868(4) 0.4821(6) 1.  0 d
  O3    O2-    4 a 0.6884(3) 0.2063(4) 0.6904(6) 1.  0 d
  O4    O2-    4 a 0.6808(3) 0.2716(4) 0.3605(6) 1.  0 d
  O5    O2-    4 a 0.2655(3) 0.1746(4) 0.0038(6) 1.  2 d
  O6    O2-    4 a 0.4716(3) 0.2478(3) 0.1992(6) 1.  2 d
  O7    O2-    4 a 0.4691(3) 0.1758(4) 0.7796(6) 1.  2 d
  O8    O2-    4 a 0.5828(3) 0.0463(4) 0.0773(6) 1.  2 d
  O9    O2-    4 a 0.3761(3) 0.9620(3) 0.8889(6) 1.  2 d
  O10   O2-    4 a 0.3622(3) 0.0342(4) 0.2907(6) 1.  2 d
  O11   O2-    4 a 0.4916(4) 0.4377(4) 0.9384(7) 1.  2 d
  H1    H1+    4 a 0.244(9) 0.229(10) 0.105(22) 1.  0 d
  H2    H1+    4 a 0.234(9) 0.206(10) 0.888(22) 1.  0 d
  H3    H1+    4 a 0.435(11) 0.27(1) 0.33(2) 1.  0 d
  H4    H1+    4 a 0.533(10) 0.246(10) 0.268(20) 1.  0 d
  H5    H1+    4 a 0.419(9) 0.234(9) 0.664(21) 1.  0 d
  H6    H1+    4 a 0.549(9) 0.188(9) 0.755(20) 1.  0 d
  H7    H1+    4 a 0.632(10) 0.055(11) 0.212(21) 1.  0 d
  H8    H1+    4 a 0.60(1) 0.983(11) 0.025(20) 1.  0 d
  H9    H1+    4 a 0.356(10) 0.906(10) 0.961(18) 1.  0 d
  H10   H1+    4 a 0.428(9) 0.946(10) 0.768(21) 1.  0 d
  H11   H1+    4 a 0.281(11) 0.033(11) 0.32(2) 1.  0 d
  H12   H1+    4 a 0.385(11) 0.008(10) 0.414(20) 1.  0 d
  H13   H1+    4 a 0.431(10) 0.492(11) 0.975(20) 1.  0 d
  H14   H1+    4 a 0.465(10) 0.370(11) 0.008(19) 1.  0 d
_refine_ls_R_factor_all            0.057