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_2102564
_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         'C8 H6 O5, H2 O'
_chemical_formula_sum            'C8 H8 O6'
_chemical_formula_weight         200.14
_chemical_melting_point          373
_chemical_name_common            '2-hydroxyisophthalic acid'
_chemical_name_systematic        '2-hydroxybenzene-1,2-dioic acid'
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
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_computing_cell_refinement       'XSCANS (Siemens, 1996)'
_computing_data_collection       'XSCANS (Siemens, 1996)'
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_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 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Siemens P4'
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_diffrn_radiation_monochromator  graphite
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_diffrn_standards_decay_%        'variation <2.0'
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_exptl_absorpt_correction_type   numerical
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_exptl_crystal_description       'square prism'
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_refine_ls_extinction_coef       0.00(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
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_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1001P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_number_gt                1574
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_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            na5013.cif
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_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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 'Triclinic' changed to 'triclinic'
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        412.87(15)
_cod_database_code               2102564
_cod_database_fobs_code          2102564