Temperature- and Pressure-Induced Proton Transfer in the 1:1 Adduct Formed between Squaric Acid and 4,4'-Bipyridine
David M. S. Martins; Derek S. Middlemiss; Colin R. Pulham; Chick C. Wilson; Mark T. Weller; Paul F. Henry; Norman Shankland; Kenneth Shankland; William G. Marshall; Richard M. Ibberson; Kevin Knight; Stephen Moggach; Michela Brunelli; Carole A. Morrison; Journal of the American Chemical Society 131 (2009) 3884–3893; doi:10.1021/ja8082973

data_4104001
_publ_contact_author_address
; 
 Chemical Crystallography Laboratory, 
 Department of Chemistry, 
 University of Edinburgh, 
 Edinburgh, EH9 2JJ, UK. 
;
_publ_contact_author_email       smoggach@staffmail.ed.ac.uk
_publ_contact_author_name        'Stephen A. Moggach'
_publ_contact_author_phone       '+44 1316 504806'
_publ_section_title
;
 Temperature- and Pressure-Induced Proton Transfer in the 1:1 Adduct
 Formed between Squaric Acid and 4,4'-Bipyridine
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              3884
_journal_page_last               3893
_journal_paper_doi               10.1021/ja8082973
_journal_volume                  131
_journal_year                    2009
_chemical_formula_moiety         'C10 H9 N2, C4 H O4'
_chemical_formula_sum            'C14 H10 N2 O4'
_chemical_formula_weight         270.24
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_date             08-09-09
_audit_creation_method           CRYSTALS_ver_12.85
_cell_angle_alpha                90
_cell_angle_beta                 92.947(7)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   3.7551(5)
_cell_length_b                   11.2066(13)
_cell_length_c                   27.322(3)
_cell_measurement_reflns_used    4554
_cell_measurement_temperature    180
_cell_measurement_theta_max      30
_cell_measurement_theta_min      2
_cell_volume                     1148.2(2)
_computing_cell_refinement       'SAINT (Siemens ,1995)'
_computing_data_collection       'SMART (Siemens, 1993)'
_computing_data_reduction        'SAINT (Siemens ,1995)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      180
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.917
_diffrn_measurement_device       'Bruker SMART'
_diffrn_measurement_device_type  Area
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.030
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -37
_diffrn_reflns_number            11800
_diffrn_reflns_theta_full        27.922
_diffrn_reflns_theta_max         29.705
_diffrn_reflns_theta_min         1.965
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.117
_exptl_absorpt_correction_T_max  0.99
_exptl_absorpt_correction_T_min  0.88
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Siemens, 1996)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.563
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             560
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.42
_refine_diff_density_min         -0.21
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.0145
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     187
_refine_ls_number_reflns         2994
_refine_ls_number_restraints     2
_refine_ls_R_factor_all          0.0524
_refine_ls_R_factor_gt           0.0420
_refine_ls_shift/su_max          0.000703
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 Method= Modified Sheldrick 
 w=1/[\s^2^(F^2^) + ( 0.06P)^2^ + 0.38P] 
 ,where P=(max(Fo^2^,0) + 2Fc^2^)/3 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1130
_refine_ls_wR_factor_gt          0.1064
_refine_ls_wR_factor_ref         0.1130
_reflns_limit_h_max              5
_reflns_limit_h_min              -5
_reflns_limit_k_max              15
_reflns_limit_k_min              0
_reflns_limit_l_max              37
_reflns_limit_l_min              0
_reflns_number_gt                2411
_reflns_number_total             2996
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   1.59
_oxford_diffrn_Wilson_scale      2.63
_oxford_refine_ls_r_factor_ref   0.0524
_oxford_refine_ls_scale          2.10(2)
_oxford_reflns_number_all        2994
_oxford_reflns_threshold_expression_ref I>-10.0\s(I)
_oxford_structure_analysis_title 'cp0508 in P2(1)/n'
_cod_data_source_file            ja8082973_si_002_180K.cif
_cod_data_source_block           180K
_cod_original_sg_symbol_Hall     '-P 2yn '
_cod_original_sg_symbol_H-M      'P 1 21/n 1 '
_cod_database_code               4104001
_cod_database_fobs_code          4104001