A polymorph of terephthalaldehyde
Teng, Lei; Wang, Zhiguo; Acta Crystallographica Section E 64 (2008) o1562–; doi:10.1107/S1600536808022381

data_2218899
_publ_section_title
;
 A polymorph of terephthalaldehyde
;
_journal_coeditor_code           BQ2093
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1562
_journal_paper_doi               10.1107/S1600536808022381
_journal_volume                  64
_journal_year                    2008
_chemical_formula_iupac          'C8 H6 O2'
_chemical_formula_moiety         'C8 H6 O2'
_chemical_formula_sum            'C8 H6 O2'
_chemical_formula_weight         134.13
_chemical_name_systematic
;
terephthalaldehyde
;
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.8811(5)
_cell_length_b                   3.8933(3)
_cell_length_c                   13.3202(9)
_cell_measurement_reflns_used    1070
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      23.49
_cell_measurement_theta_min      3.06
_cell_volume                     668.01(7)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT (Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL (Sheldrick, 2008)'
_computing_publication_material  'SHELXTL (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      295(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker SMART 4K CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_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  0.0297
_diffrn_reflns_av_sigmaI/netI    0.0189
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       -4
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            3959
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         3.06
_exptl_absorpt_coefficient_mu    0.096
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.334
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             280
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.163
_refine_diff_density_min         -0.100
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.044
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     91
_refine_ls_number_reflns         653
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.043
_refine_ls_R_factor_all          0.0498
_refine_ls_R_factor_gt           0.0424
_refine_ls_shift/su_max          0.014
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0755P)^2^+0.0133P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1076
_refine_ls_wR_factor_ref         0.1120
_reflns_number_gt                563
_reflns_number_total             653
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bq2093.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P ca 21'
_cod_database_code               2218899
_cod_database_fobs_code          2218899