Temperature-induced reversible structural phase transition of 1,4-dimethyl-1,4-diazabicyclo[2.2.2]octane bis(perchlorate)
chen, lizhuang; Cao, Xing-Xing; Huang, Deng-Deng; Pan, Qi-Jian; RSC Adv.  (2015) –; doi:10.1039/C5RA07526B

data_7220768
_publ_section_title
;
 Temperature-induced reversible structural phase transition of
 1,4-dimethyl-1,4-diazabicyclo[2.2.2]octane bis(perchlorate)
;
_journal_name_full               'RSC Adv.'
_journal_paper_doi               10.1039/C5RA07526B
_journal_year                    2015
_chemical_formula_sum            'C8 H18 Cl2 N2 O8'
_chemical_formula_weight         341.14
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           62
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2n'
_symmetry_space_group_name_H-M   'P n m a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2015-01-20 deposited with the CCDC.
2015-06-12 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            12
_cell_length_a                   15.5417(14)
_cell_length_b                   13.3677(12)
_cell_length_c                   20.7728(19)
_cell_measurement_reflns_used    7167
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      23.56
_cell_measurement_theta_min      2.36
_cell_volume                     4315.7(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0307
_diffrn_reflns_av_unetI/netI     0.0179
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            32689
_diffrn_reflns_theta_full        25.68
_diffrn_reflns_theta_max         25.68
_diffrn_reflns_theta_min         1.64
_exptl_absorpt_coefficient_mu    0.489
_exptl_absorpt_correction_T_max  0.9085
_exptl_absorpt_correction_T_min  0.8672
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_density_diffrn    1.575
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             2136
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.564
_refine_diff_density_min         -0.632
_refine_diff_density_rms         0.076
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     471
_refine_ls_number_reflns         4284
_refine_ls_number_restraints     278
_refine_ls_restrained_S_all      1.116
_refine_ls_R_factor_all          0.1060
_refine_ls_R_factor_gt           0.0787
_refine_ls_shift/su_max          0.010
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0701P)^2^+11.6493P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1863
_refine_ls_wR_factor_ref         0.2117
_reflns_number_gt                3016
_reflns_number_total             4284
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c5ra07526b2.cif
_cod_data_source_block           w1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 3271 2015-04-21 07:52:19Z andrius 
;
_cod_original_sg_symbol_H-M      'Pnma '
_cod_database_code               7220768