On the crystal chemistry of olivine-type germanate compounds, Ca~1+<i>x~</i><i>M</i>~1{-~<i>x</i>}GeO~4~ (<i>M</i>^2+^ = Ca, Mg, Co, Mn)
Redhammer, Günther J.; Roth, Georg; Amthauer, Georg; Lottermoser, Werner; Acta Crystallographica Section B 64 (2008) 261–271; doi:10.1107/S0108768108010434

data_2104153
_publ_section_title
;
 On the crystal chemistry of olivine-type germanate compounds,
 Ca~1+<i>x~</i><i>M</i>~1{-~<i>x</i>}GeO~4~ (<i>M</i>^2+^ = Ca, Mg, Co,
 Mn)
;
_journal_coeditor_code           WS5059
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              261
_journal_page_last               271
_journal_paper_doi               10.1107/S0108768108010434
_journal_volume                  64
_journal_year                    2008
_chemical_formula_moiety         'Ge O4, 1.07(Ca)0.93(Mg)'
_chemical_formula_sum            'Ca1.07 Ge Mg0.93 O4'
_chemical_formula_weight         202.04
_space_group_crystal_system      orthorhombic
_space_group_IT_number           62
_space_group_name_Hall           '-P 2ac 2n'
_space_group_name_H-M_alt        'P n m a'
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.2882(7)
_cell_length_b                   6.4309(4)
_cell_length_c                   5.0223(3)
_cell_measurement_reflns_used    3967
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      28.7
_cell_measurement_theta_min      3.61
_cell_volume                     364.59(4)
_computing_cell_refinement       'Bruker SAINT+ (Bruker, 2001)'
_computing_data_collection       'Bruker SMART+ (Bruker, 2001)'
_computing_data_reduction        'Bruker SAINT+ (Bruker, 2001)'
_computing_molecular_graphics    'Diamonds 3.0 (Pennington,1999)'
_computing_publication_material  'WinGX v1.70.01 (Farrugia 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device       '3-circle diffractometer'
_diffrn_measurement_device_type  'SMART APEX'
_diffrn_measurement_method
'rotation, \w-scans at 4 different \f positions'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.097
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            3967
_diffrn_reflns_theta_full        28.3
_diffrn_reflns_theta_max         28.3
_diffrn_reflns_theta_min         3.61
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    9.922
_exptl_absorpt_correction_T_max  0.50
_exptl_absorpt_correction_T_min  0.46
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
'via equivalents using X-SHAPE (Stoe & Cie 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    3.682
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       cube
_exptl_crystal_F_000             386.2
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.738
_refine_diff_density_min         -1.372
_refine_ls_extinction_coef       0.0044(15)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.16
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     45
_refine_ls_number_reflns         487
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.158
_refine_ls_R_factor_gt           0.0259
_refine_ls_shift/su_max          0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0238P)^2^+0.2954P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.0536
_reflns_number_gt                476
_reflns_number_total             487
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ws5059.cif
_cod_data_source_block           ca2mg_1
_cod_database_code               2104153
_cod_database_fobs_code          2104153