Combined Effect of Germanium Doping and Grain Alignment on Oxide-Ion Conductivity of Apatite-Type Lanthanum Silicate Polycrystal
Fukuda, Koichiro; Asaka, Toru; Ishizawa, Nobuo; Mino, Hiroki; Urushihara, Daisuke; Berghout, Abid; Béchade, Emilie; Masson, Olivier; Julien, Isabelle; Thomas, Philippe; Chemistry of Materials 24 (2012) 2611–; doi:10.1021/cm301484q

data_4001671
_publ_section_title
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 Combined Effect of Germanium Doping and Grain Alignment on Oxide-Ion
 Conductivity of Apatite-Type Lanthanum Silicate Polycrystal
;
_journal_issue                   13
_journal_name_full               'Chemistry of Materials'
_journal_page_first              2611
_journal_paper_doi               10.1021/cm301484q
_journal_volume                  24
_journal_year                    2012
_chemical_formula_moiety         'Ge0.77 La9.33 O14 Si5.23, 12(O)'
_chemical_formula_sum            'Ge0.77 La9.33 O26 Si5.23'
_chemical_formula_weight         1914.7
_space_group_IT_number           176
_symmetry_cell_setting           hexagonal
_symmetry_Int_Tables_number      176
_symmetry_space_group_name_Hall  '-P 6c'
_symmetry_space_group_name_H-M   'P 63/m'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            1
_cell_length_a                   9.7508(2)
_cell_length_b                   9.7508(2)
_cell_length_c                   7.2153(1)
_cell_measurement_reflns_used    9966
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      45.30
_cell_measurement_theta_min      2.41
_cell_volume                     594.108(19)
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1
_diffrn_measured_fraction_theta_max 1
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0216
_diffrn_reflns_av_sigmaI/netI    0.0097
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            21510
_diffrn_reflns_theta_full        45.3
_diffrn_reflns_theta_max         45.3
_diffrn_reflns_theta_min         2.41
_exptl_absorpt_coefficient_mu    17.691
_exptl_absorpt_correction_T_max  0.838
_exptl_absorpt_correction_T_min  0.809
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_density_diffrn    5.3476
_exptl_crystal_F_000             836.5
_exptl_crystal_size_max          0.015
_exptl_crystal_size_mid          0.01
_exptl_crystal_size_min          0.01
_refine_diff_density_max         0.49
_refine_diff_density_min         -0.65
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_gt    1.38
_refine_ls_goodness_of_fit_ref   1.35
_refine_ls_number_constraints    6
_refine_ls_number_parameters     74
_refine_ls_number_reflns         1759
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0154
_refine_ls_R_factor_gt           0.0121
_refine_ls_shift/su_max          0.0281
_refine_ls_shift/su_mean         0.0045
_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          0.0183
_refine_ls_wR_factor_ref         0.0189
_reflns_number_gt                1567
_reflns_number_total             1759
_reflns_threshold_expression     I>3\s(I)
_cod_data_source_file            cm301484q_si_002.cif
_cod_data_source_block           global
_cod_original_cell_volume        594.11(2)
_cod_database_code               4001671
_atom_site_anharm_details
;
The atomic anharmonic pdf is approximated by a Gram-Charlier expansion
about the harmonic pdf, according to the expression :

      P(u) = (1 + Cijk*Hijk/3! + Dijkl*Hijkl/4!)*P(0)

The coefficients Cijk and Dijkl are refined in the least squares procedure.
The reported coefficients Cijk are multiplied by 1000 and Dijkl by 10000.
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