Temperature-induced order-disorder structural phase transitions of two-dimensional isostructural hexamethylenetetramine co-crystals.
Chia, Tze Shyang; Quah, Ching Kheng; Acta crystallographica Section B, Structural science, crystal engineering and materials 73 (2017) 879–890; doi:10.1107/S2052520617009520

data_2311768
_publ_section_title
;
 Temperature-induced order-disorder structural phase transitions of
 two-dimensional isostructural hexamethylenetetramine co-crystals.
;
_journal_issue                   'Pt 5'
_journal_name_full
'Acta crystallographica Section B, Structural science, crystal engineering and materials'
_journal_page_first              879
_journal_page_last               890
_journal_paper_doi               10.1107/S2052520617009520
_journal_volume                  73
_journal_year                    2017
_chemical_formula_moiety         'C6 H12 N4, 2(C7 H6 O2)'
_chemical_formula_sum            'C20 H24 N4 O4'
_chemical_formula_weight         384.43
_chemical_name_systematic
;
Hexamethylenetetramine bis(benzoic acid)
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           7
_space_group_name_Hall           'P -2yac'
_space_group_name_H-M_alt        'P 1 n 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 99.654(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.1457(8)
_cell_length_b                   26.765(3)
_cell_length_c                   12.0716(16)
_cell_measurement_reflns_used    7036
_cell_measurement_temperature    250.0(1)
_cell_measurement_theta_max      28.05
_cell_measurement_theta_min      2.85
_cell_volume                     1957.5(4)
_computing_cell_refinement       'SAINT (Bruker, 2009)'
_computing_data_collection       'APEX2 (Bruker, 2009)'
_computing_data_reduction        'SAINT (Bruker, 2009)'
_computing_molecular_graphics
;
SHELXTL (Sheldrick, 2008), Mercury (Macrae <i>et al.</i>, 2008)
;
_computing_publication_material
;
PLATON (Spek, 2009)
;
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXS-2013 (Sheldrick, 2008)'
_diffrn_ambient_temperature      250.0(1)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker APEX Duo CCD area detector'
_diffrn_measurement_method       '\f and \w 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  0.0487
_diffrn_reflns_av_unetI/netI     0.0339
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       35
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            6406
_diffrn_reflns_point_group_measured_fraction_full 0.501
_diffrn_reflns_point_group_measured_fraction_max 0.498
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         28.271
_diffrn_reflns_theta_min         1.873
_exptl_absorpt_coefficient_mu    0.093
_exptl_absorpt_correction_T_max  0.936488
_exptl_absorpt_correction_T_min  0.755271
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(<i>TWINABS</i>; Sheldrick, 2012)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.304
_exptl_crystal_description       block
_exptl_crystal_F_000             816
_exptl_crystal_size_max          0.756
_exptl_crystal_size_mid          0.389
_exptl_crystal_size_min          0.208
_refine_diff_density_max         0.175
_refine_diff_density_min         -0.146
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details
;
No quotients, so Flack parameter determined by classical intensity fit
;
_refine_ls_abs_structure_Flack   -1.6(11)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.051
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     522
_refine_ls_number_reflns         4828
_refine_ls_number_restraints     6
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.0856
_refine_ls_R_factor_gt           0.0506
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0476P)^2^+0.3800P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1111
_refine_ls_wR_factor_ref         0.1284
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    0.000
_reflns_Friedel_fraction_max     0.000
_reflns_number_gt                3264
_reflns_number_total             4828
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            gw5053sup1.cif
_cod_data_source_block           1533069
_cod_original_cell_volume        1957.6(4)
_cod_original_sg_symbol_H-M      'P n'
_cod_database_code               2311768
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.933
_shelx_estimated_absorpt_t_max   0.981
_exptl_absorpt_special_details
; 
The crystal was placed in the cold stream of an Oxford Cryosystems 
Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating 
at 250.0 (1) K.
;
_shelx_res_checksum              82435
_shelx_hkl_checksum              75883