Binary Boron-Rich Borides of Magnesium: Single-Crystal Investigations and Properties of MgB7 and the New Boride Mg~5B44
Alexis Pediaditakis; Melanie Schroeder; Vanessa Sagawe; Thilo Ludwig; Harald Hillebrecht; Inorganic Chemistry 49 (2010) 10882–10893; doi:10.1021/ic1012389

data_4317140
_publ_contact_author_address
;
 Albert-Ludwigs-Universit\"at Freiburg
 Institut f\"ur Anorganische und Analytische Chemie
 Albertstr. 21
 D-79104 Freiburg
 Germany
;
_publ_contact_author_email       harald.hillebrecht@ac.uni-freiburg.de
_publ_contact_author_fax         +49-(0)761-203-6012
_publ_contact_author_name        'Prof. Dr. Harald Hillebrecht'
_publ_contact_author_phone       +49-(0)761-203-6131
_publ_section_title
;
 Binary Boron-Rich Borides of Magnesium: Single-Crystal Investigations and
 Properties of MgB7 and the New Boride Mg~5B44
;
_journal_name_full               'Inorganic Chemistry'
_journal_page_first              10882
_journal_page_last               10893
_journal_paper_doi               10.1021/ic1012389
_journal_volume                  49
_journal_year                    2010
_chemical_formula_sum            'B44 Mg5'
_chemical_formula_weight         597.19
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           92
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'P 4abw 2nw'
_symmetry_space_group_name_H-M   'P 41 21 2'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.3795(15)
_cell_length_b                   10.3795(15)
_cell_length_c                   14.391(3)
_cell_measurement_reflns_used    37984
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      37.5
_cell_measurement_theta_min      3
_cell_volume                     1550.4(5)
_computing_cell_refinement       'Software for IPDS-II, Fa. Stoe'
_computing_data_collection       'Software for IPDS-II, Fa. Stoe'
_computing_data_reduction        'Software for IPDS-II, Fa. Stoe'
_computing_molecular_graphics    'Diamond (Crystal impact, 2005)'
_computing_publication_material  'SHELXL-97_(Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_type            Curved_image_plate
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_details
;
120_frames_with_4.5_min
w=48_degree,c=54 degree,f=0_degree,Dw=1.2_degree
120_frames_with_4.5_min
w=50_degree,c=54 degree,f=0_degree,Dw=1.2_degree
;
_diffrn_measurement_device_type  Rigaku_R-axis_Spider
_diffrn_measurement_method       rotation_method
_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    0.0209
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            30361
_diffrn_reflns_theta_full        37.50
_diffrn_reflns_theta_max         37.50
_diffrn_reflns_theta_min         3.12
_exptl_absorpt_coefficient_mu    0.288
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            dark_metallic
_exptl_crystal_density_diffrn    2.558
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       irregular_fragment
_exptl_crystal_F_000             1120
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.369
_refine_diff_density_min         -0.297
_refine_diff_density_rms         0.063
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.03(10)
_refine_ls_extinction_coef       0.000(3)
_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   1.143
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     251
_refine_ls_number_reflns         4080
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.143
_refine_ls_R_factor_all          0.0265
_refine_ls_R_factor_gt           0.0251
_refine_ls_shift/su_max          6.532
_refine_ls_shift/su_mean         0.026
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0294P)^2^+0.3455P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0634
_refine_ls_wR_factor_ref         0.0640
_reflns_number_gt                3933
_reflns_number_total             4080
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ic1012389_si_002_1.cif
_cod_data_source_block           mg5b44
_cod_original_cell_volume        1550.4(4)
_cod_database_code               4317140