A low-temperature redetermination of metaldehyde
Barnett, Sarah A.; Hulme, Ashley T.; Tocher, Derek A.; Acta Crystallographica Section E 61 (2005) o857–o859; doi:10.1107/S1600536805006306

data_2205445
_publ_section_title
;
 A low-temperature redetermination of metaldehyde
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o857
_journal_page_last               o859
_journal_paper_doi               10.1107/S1600536805006306
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C8 H16 O4'
_chemical_formula_moiety         'C8 H16 O4'
_chemical_formula_sum            'C8 H16 O4'
_chemical_formula_weight         176.21
_chemical_name_common            metaldehyde
_chemical_name_systematic
;
2,4,6,8-tetramethyl-1,3,5,7-tetroxocane
;
_space_group_IT_number           79
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'I 4'
_symmetry_space_group_name_H-M   'I 4'
_atom_sites_solution_hydrogens   difmap
_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            2
_cell_length_a                   10.4974(10)
_cell_length_b                   10.4974(10)
_cell_length_c                   4.0967(7)
_cell_measurement_reflns_used    1875
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      28.296
_cell_measurement_theta_min      2.744
_cell_volume                     451.44(10)
_computing_cell_refinement       'SAINT (Bruker, 1998)'
_computing_data_collection       'SMART (Bruker, 1998)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.978
_diffrn_measurement_device_type  'Bruker SMART APEX'
_diffrn_measurement_method       '\w rotation with narrow frames'
_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  0.0167
_diffrn_reflns_av_sigmaI/netI    0.0153
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            1953
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         28.30
_diffrn_reflns_theta_min         2.74
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9777
_exptl_absorpt_correction_T_min  0.8831
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.296
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Needle
_exptl_crystal_F_000             192
_exptl_crystal_size_max          1.24
_exptl_crystal_size_mid          0.39
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.172
_refine_diff_density_min         -0.182
_refine_ls_extinction_coef       0.103(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.079
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     45
_refine_ls_number_reflns         314
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.077
_refine_ls_R_factor_all          0.0289
_refine_ls_R_factor_gt           0.0288
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0515P)^2^+0.1168P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0732
_refine_ls_wR_factor_ref         0.0732
_reflns_number_gt                312
_reflns_number_total             314
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ci6537.cif
_cod_data_source_block           I
_cod_database_code               2205445
_cod_database_fobs_code          2205445