When is a polymorph not a polymorph? Helical trimeric O–H···O synthons in trans-1,4-diethynylcyclohexane-1,4-diol
Bilton, Clair; Howard, Judith A. K.; Laxmi Madhavi, N. N.; Nangia, Ashwini; Desiraju, Gautam R.; Allen, Frank H.; Wilson, Chick C.; Chemical Communications  (1999) 1675–; doi:10.1039/a905025f

data_7110633
_publ_section_title
;
 When is a polymorph not a polymorph? Helical trimeric
 O--H&#x00B7;&#x00B7;&#x00B7;O synthons in
 trans-1,4-diethynylcyclohexane-1,4-diol
;
_journal_issue                   17
_journal_name_full               'Chemical Communications'
_journal_page_first              1675
_journal_paper_doi               10.1039/a905025f
_journal_year                    1999
_chemical_formula_moiety         'C10 H12 O2'
_chemical_formula_sum            'C10 H12 O2'
_chemical_formula_weight         164.20
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                103.005(2)
_cell_angle_beta                 93.424(2)
_cell_angle_gamma                94.572(2)
_cell_formula_units_Z            3
_cell_length_a                   6.2074(3)
_cell_length_b                   10.0187(5)
_cell_length_c                   11.5666(5)
_cell_measurement_reflns_used    999
_cell_measurement_temperature    150
_cell_measurement_theta_max      30.69
_cell_measurement_theta_min      10.26
_cell_volume                     696.41(6)
_computing_cell_refinement       'Brucker SMART'
_computing_data_collection       'Brucker SMART'
_computing_data_reduction        'Brucker SAINT'
_computing_molecular_graphics    'SHELXL-97 (Sheldrick, 1997)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      150
_diffrn_detector_area_resol_mean 'not relevant'
_diffrn_measured_fraction_theta_full 0.865
_diffrn_measured_fraction_theta_max 0.865
_diffrn_measurement_device_type  'Brucker SMART CCD'
_diffrn_measurement_method       '\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  0.0255
_diffrn_reflns_av_sigmaI/netI    0.0255
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            5564
_diffrn_reflns_theta_full        30.33
_diffrn_reflns_theta_max         30.33
_diffrn_reflns_theta_min         1.81
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_T_max  0.332
_exptl_absorpt_correction_T_min  0.284
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'empirical using psi-scans'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.175
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             264
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.4
_refine_diff_density_max         0.216
_refine_diff_density_min         -0.280
_refine_diff_density_rms         0.050
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.046
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     235
_refine_ls_number_reflns         3618
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.0511
_refine_ls_R_factor_gt           0.0409
_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^)+(0.0573P)^2^+0.1318P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1026
_refine_ls_wR_factor_ref         0.1089
_reflns_number_gt                3027
_reflns_number_total             3618
_reflns_threshold_expression     2sigma(I)
_cod_data_source_file            905025fsup1.cif
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               7110633