Structure of synthetic K-rich birnessite obtained by high-temperature decomposition of KMnO4. I. Two-layer polytype from 800 C experiments.
Gaillot, Anne-Claire; Flot, David; Drits, Victor A.; Burghammer, Manfred; Manceau, Alain; Lanson, Bruno; Chemistry of Materials  (2003) –; doi:10.1021/cm021733g

data_4000330
_publ_section_title
;
 Structure of synthetic K-rich birnessite obtained by high-temperature
decomposition of KMnO4.
I. Two-layer polytype from 800 C experiments.
;
_journal_name_full               'Chemistry of Materials'
_journal_paper_doi               10.1021/cm021733g
_journal_year                    2003
_chemical_formula_moiety         'K1 Mn2 O5'
_chemical_formula_sum            'K Mn2 O5.44'
_chemical_formula_weight         236.02
_space_group_IT_number           194
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  '-P 6c 2c'
_symmetry_space_group_name_H-M   'P 63/m m c'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            1
_cell_length_a                   2.840(1)
_cell_length_b                   2.840(1)
_cell_length_c                   14.030(6)
_cell_measurement_reflns_used    1523
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.8
_cell_measurement_theta_min      8.52
_cell_volume                     98.00(6)
_diffrn_detector_area_resol_mean 15.52
_diffrn_detector_type            marCCD
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'ESRF/EMBL microdiffractometer'
_diffrn_measurement_method       oscillation
_diffrn_radiation_monochromator  'Si 111'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_source         'ESRF-ID13 beamline'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.729
_diffrn_reflns_av_R_equivalents  0.0448
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            6727
_diffrn_reflns_theta_full        41.4
_diffrn_reflns_theta_max         41.4
_diffrn_reflns_theta_min         8.52
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    7.415
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            black
_exptl_crystal_density_diffrn    3.999
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             113
_exptl_crystal_size_max          0.003
_exptl_crystal_size_mid          0.003
_exptl_crystal_size_min          0.0005
_refine_diff_density_max         0.971
_refine_diff_density_min         -0.393
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     14
_refine_ls_number_reflns         153
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_gt           0.0275
_refine_ls_shift/su_max          0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0344P)^2^+0.1787P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.0696
_reflns_number_gt                137
_reflns_number_total             153
_reflns_threshold_expression     >2sigma(I)
_cod_database_code               4000330