1,4-Bis(4-methoxyphenyl)piperazine-2,5-dione
Yong-Hong Wen; Shu-Sheng Zhang; Bao-Hui Yu; Xue-Mei Li; Acta Crystallographica Section E 60 (2004) o1494–o1496; doi:10.1107/S1600536804018914

data_2204153
_publ_section_title
;
 1,4-Bis(4-methoxyphenyl)piperazine-2,5-dione
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1494
_journal_page_last               o1496
_journal_paper_doi               10.1107/S1600536804018914
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'C18 H18 N2 O4'
_chemical_formula_moiety         'C18 H18 N2 O4'
_chemical_formula_sum            'C18 H18 N2 O4'
_chemical_formula_weight         326.24
_chemical_name_systematic
;
1,4-Bis(4-methoxyphenyl)piperazine-2,5-dione
;
_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                 92.687(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   16.9231(17)
_cell_length_b                   5.8166(6)
_cell_length_c                   8.0580(8)
_cell_measurement_reflns_used    4504
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      26.05
_cell_measurement_theta_min      2.41
_cell_volume                     792.32(14)
_computing_cell_refinement       'SAINT (Siemens, 1996)'
_computing_data_collection       'SMART (Siemens, 1996)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    SHELXTL
_computing_publication_material
;
SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990)
;
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type
;
Simens SMART 1000 CCD area-detector diffractometer
;
_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  0.0177
_diffrn_reflns_av_sigmaI/netI    0.0204
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            4225
_diffrn_reflns_theta_full        26.05
_diffrn_reflns_theta_max         26.05
_diffrn_reflns_theta_min         2.41
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.098
_exptl_absorpt_correction_T_max  0.9817
_exptl_absorpt_correction_T_min  0.9601
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.368
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Column
_exptl_crystal_F_000             344
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.21
_exptl_crystal_size_min          0.19
_refine_diff_density_max         0.154
_refine_diff_density_min         -0.151
_refine_ls_extinction_coef       0.028(5)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.042
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     146
_refine_ls_number_reflns         1557
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.042
_refine_ls_R_factor_all          0.0493
_refine_ls_R_factor_gt           0.0423
_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^)+(0.0631P)^2^+0.1534P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1129
_refine_ls_wR_factor_ref         0.1194
_reflns_number_gt                1318
_reflns_number_total             1557
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            cv6347.cif
_cod_data_source_block           I
_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_sg_symbol_H-M      'P 21/c'
_cod_database_code               2204153
_cod_database_fobs_code          2204153