2-Hydroxyisophthalic acid: hydrogen-bonding patterns in the monohydrate and the tetraphenylphosphonium salt. An instance of dramatic acidity enhancement by symmetric, internally hydrogen-bonded anion stabilization
Bawa, Shaleen; Coté, Marie L.; Dubois, Patrick; Lalancette, Roger A.; Thompson, Hugh W.; Acta Crystallographica Section B 60 (2004) 438–446; doi:10.1107/S0108768104012686

data_2102565
_publ_section_title
;
 2-Hydroxyisophthalic acid: hydrogen-bonding patterns in the
 monohydrate and the tetraphenylphosphonium salt. An instance of
 dramatic acidity enhancement by symmetric, internally hydrogen-bonded
 anion stabilization
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              438
_journal_page_last               446
_journal_paper_doi               10.1107/S0108768104012686
_journal_volume                  60
_journal_year                    2004
_chemical_formula_moiety         'C24 H20 P, C8 H5 O5'
_chemical_formula_sum            'C32 H25 O5 P'
_chemical_formula_weight         520.49
_chemical_melting_point          446
_chemical_name_common
;
 Tetraphenylphosphonium 2-hydroxyisophthalate
;
_chemical_name_systematic
;
 tetraphenylphosphonium 2-hydroxybenzene-1,3-dioate
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 101.15(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   15.287(5)
_cell_length_b                   8.027(3)
_cell_length_c                   22.144(7)
_cell_measurement_reflns_used    22
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      10.5
_cell_measurement_theta_min      4.1
_cell_volume                     2666.0(16)
_computing_cell_refinement       'XSCANS (Siemens, 1996)'
_computing_data_collection       'XSCANS (Siemens, 1996)'
_computing_data_reduction        'XSCANS (Siemens, 1996)'
_computing_molecular_graphics    'SHELXP-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      296(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Siemens P4'
_diffrn_measurement_method       '2\q/\q 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  0.0313
_diffrn_reflns_av_sigmaI/netI    0.0866
_diffrn_reflns_limit_h_max       1
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       1
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            6087
_diffrn_reflns_theta_full        25.01
_diffrn_reflns_theta_max         25.01
_diffrn_reflns_theta_min         2.09
_diffrn_standards_decay_%        'variation <1.3'
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.143
_exptl_absorpt_correction_T_max  0.97
_exptl_absorpt_correction_T_min  0.94
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'Sheldrick (1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.297
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1088
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.44
_exptl_crystal_size_min          0.26
_refine_diff_density_max         0.17
_refine_diff_density_min         -0.24
_refine_ls_extinction_coef       0.0030(5)
_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   1.01
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     350
_refine_ls_number_reflns         4707
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.01
_refine_ls_R_factor_all          0.133
_refine_ls_R_factor_gt           0.063
_refine_ls_shift/su_max          0.00
_refine_ls_shift/su_mean         0.00
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0417P)^2^+0.5629P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.113
_refine_ls_wR_factor_ref         0.137
_reflns_number_gt                2544
_reflns_number_total             4707
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            na5013.cif
_cod_data_source_block           2
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        2665.7(15)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2102565
_cod_database_fobs_code          2102565