A Low-Temperature Phase of 2-Pyrrolidone
Richard Goddard; Oliver Heinemann; Carl Krüger; Ildikó Magdó; Franz Mark; Kurt Schaffner; Acta Crystallographica Section C 54 (1998) 501–504; doi:10.1107/S010827019701651X

data_2007152
_publ_section_title
;
 A Low-Temperature Phase of 2-Pyrrolidone
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              501
_journal_page_last               504
_journal_paper_doi               10.1107/S010827019701651X
_journal_volume                  54
_journal_year                    1998
_chemical_formula_structural     '(C3 H6) (N H) (C O)'
_chemical_formula_sum            'C4 H7 N O'
_chemical_formula_weight         85.11
_chemical_melting_point          12.0
_chemical_name_common            pyrrolidone
_chemical_name_systematic
;
 Pyrrolidin-2-one (1-aza-2-cyclopentanone)
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_cell_angle_alpha                85.86(2)
_cell_angle_beta                 73.20(3)
_cell_angle_gamma                73.44(3)
_cell_formula_units_Z            2
_cell_length_a                   4.901(2)
_cell_length_b                   6.246(2)
_cell_length_c                   7.748(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    173
_cell_measurement_theta_max      32.3
_cell_measurement_theta_min      16.6
_cell_volume                     217.62(15)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection       'CAD-4 EXPRESS (Enraf-Nonius, 1995)'
_computing_data_reduction
'DATAP (Coppens, Leiserowitz & Rabinovich, 1965)'
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100
_diffrn_measurement_device       'Enraf-Nonius CAD4'
_diffrn_measurement_method       '\w-2\q scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0848
_diffrn_reflns_av_sigmaI/netI    0.0448
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1346
_diffrn_reflns_theta_max         29.92
_diffrn_reflns_theta_min         2.75
_diffrn_standards_decay_%        10.7
_diffrn_standards_interval_time  30
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.094
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.299
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    none
_exptl_crystal_description       prism
_exptl_crystal_F_000             92
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.455
_refine_diff_density_min         -0.362
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.228
_refine_ls_goodness_of_fit_obs   1.273
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     83
_refine_ls_number_reflns         1259
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.228
_refine_ls_restrained_S_obs      1.273
_refine_ls_R_factor_all          0.0761
_refine_ls_R_factor_obs          .0664
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.1190P)^2^+0.0425P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.2059
_refine_ls_wR_factor_obs         .1946
_reflns_number_observed          1057
_reflns_number_total             1259
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            cf1205.cif
_cod_data_source_block           manuscript
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'none' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.1190P)^2^+0.0425P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to 'w =
1/[\s^2^(Fo^2^)+(0.1190P)^2^+0.0425P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        217.62(13)
_cod_database_code               2007152