Reinvestigation of eakerite, Ca~2~SnAl~2~Si~6~O~18~(OH)~2~·2H~2~O: H-atom positions by single-crystal X-ray diffraction and correlation with Raman spectroscopic data
Uchida, Hinako; Downs, Robert T.; Thompson, Richard M.; Acta Crystallographica Section E 63 (2007) i47–i49; doi:10.1107/S1600536807002000

data_2212176
_publ_section_title
;
 Reinvestigation of eakerite,
 Ca~2~SnAl~2~Si~6~O~18~(OH)~2~&#x00B7;2H~2~O: H-atom positions by
 single-crystal X-ray diffraction and correlation with Raman
 spectroscopic data
;
_journal_coeditor_code           HB2229
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              i47
_journal_page_last               i49
_journal_paper_doi               10.1107/S1600536807002000
_journal_volume                  63
_journal_year                    2007
_chemical_formula_iupac          'Ca2 Sn Al2 Si6 O18 (O H)2, 2H2 O'
_chemical_formula_moiety         'Al2 H2 O20 Si6 Sn, 2(H2 O), 2(Ca)'
_chemical_formula_sum            'Al2 Ca2 H6 O22 Si6 Sn'
_chemical_formula_weight         779.40
_chemical_name_common            eakerite
_chemical_name_systematic
;
dicalcium tin dialuminosilicate dihydroxide dihydrate
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yab'
_symmetry_space_group_name_H-M   'P 1 21/a 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 101.293(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   15.8202(5)
_cell_length_b                   7.6963(3)
_cell_length_c                   7.4449(3)
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      39.8
_cell_measurement_theta_min      2.8
_cell_volume                     888.92(6)
_computing_cell_refinement       APEX2
_computing_data_collection       'APEX2 (Bruker, 1997)'
_computing_data_reduction        'SAINT (Bruker, 2005)'
_computing_molecular_graphics    'XTALDRAW (Downs & Hall-Wallace, 2003)'
_computing_publication_material  'SHELXTL (Bruker, 1997)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      295(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker APEX2 CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0344
_diffrn_reflns_av_sigmaI/netI    0.0342
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            24042
_diffrn_reflns_theta_full        39.79
_diffrn_reflns_theta_max         39.79
_diffrn_reflns_theta_min         2.79
_exptl_absorpt_coefficient_mu    2.638
_exptl_absorpt_correction_T_max  0.823
_exptl_absorpt_correction_T_min  0.776
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 2005)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.912
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             764
_exptl_crystal_size_max          0.096
_exptl_crystal_size_mid          0.087
_exptl_crystal_size_min          0.074
_refine_diff_density_max         0.877
_refine_diff_density_min         -1.149
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     163
_refine_ls_number_reflns         5432
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0358
_refine_ls_R_factor_gt           0.0267
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0266P)^2^+0.728P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0625
_refine_ls_wR_factor_ref         0.0656
_reflns_number_gt                4547
_reflns_number_total             5432
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            hb2229.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/a'
_cod_database_code               2212176