Vacancy pairing and superstructure in the high-pressure silicate K~1.5~Mg~2~Si~2~O~7~H~0.5~: a new potential host for potassium in the deep Earth
Welch, M. D.; Bindi, L.; Petříček, V.; Plášil, J.; Acta Crystallographica Section B 72 (2016) 822–827; doi:10.1107/S2052520616014049

data_2020662
_publ_section_title
;
 Vacancy pairing and superstructure in the high-pressure silicate
 K~1.5~Mg~2~Si~2~O~7~H~0.5~: a new potential host for potassium in the
 deep Earth
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              822
_journal_page_last               827
_journal_paper_doi               10.1107/S2052520616014049
_journal_volume                  72
_journal_year                    2016
_chemical_formula_sum            'H0 K1.5 Mg2 O7 Si2'
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_chemical_name_systematic        ' ?'
_space_group_IT_number           63
_space_group_ssg_name            Cmcm(0\b0)s00
_symmetry_cell_setting           orthorhombic
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_symmetry_space_group_name_H-M   'C m c m'
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_cell_angle_beta                 90
_cell_angle_gamma                90
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_cell_length_b                   5.0703(7)
_cell_length_c                   13.2505(11)
_cell_measurement_temperature    293
_cell_modulation_dimension       1
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_diffrn_detector                 eos
_diffrn_measurement_device       '4-circle X-ray diffractometer'
_diffrn_measurement_device_type  Xcalibur
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'X-ray tube'
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_diffrn_reflns_limit_h_min       -11
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_diffrn_reflns_limit_index_m_1_min -4
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_diffrn_reflns_limit_k_min       -7
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_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            19703
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_exptl_absorpt_correction_T_min  0.907
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.1076
_exptl_crystal_description       plate
_exptl_crystal_F_000             546
_exptl_crystal_size_max          0.235
_exptl_crystal_size_mid          0.175
_exptl_crystal_size_min          0.055
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_gt    2.00
_refine_ls_goodness_of_fit_ref   1.59
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_constraints    0
_refine_ls_number_parameters     98
_refine_ls_number_reflns         6596
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.1460
_refine_ls_R_factor_gt           0.0688
_refine_ls_shift/su_max          0.0278
_refine_ls_shift/su_mean         0.0027
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     w=1/(\s^2^(F)+0.0001F^2^)
_refine_ls_weighting_scheme      sigma
_refine_ls_wR_factor_gt          0.0826
_refine_ls_wR_factor_ref         0.1068
_reflns_number_gt                2500
_reflns_number_total             6596
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            xk5031sup2.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:

'_diffrn_radiation_probe' value 'X-ray' changed to 'x-ray' according
to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/IUCr/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 2020661--2020662.cif.
;
_cod_database_code               2020662
_jana_cell_commen_supercell_matrix_1_1 1
_jana_cell_commen_supercell_matrix_1_2 0
_jana_cell_commen_supercell_matrix_1_3 0
_jana_cell_commen_supercell_matrix_2_1 0
_jana_cell_commen_supercell_matrix_2_2 4
_jana_cell_commen_supercell_matrix_2_3 0
_jana_cell_commen_supercell_matrix_3_1 0
_jana_cell_commen_supercell_matrix_3_2 0
_jana_cell_commen_supercell_matrix_3_3 1
_jana_cell_commen_t_section_1    0.062