Unusual conformation of (<i>R</i>,<i>R</i>)-<i>N</i>,<i>N</i>,<i>N</i>',<i>N</i>'-tetramethyltartramide (I) and its <i>O</i>,<i>O</i>'-dibenzoyl derivative (II)
Rychlewska, U.; Acta Crystallographica Section C 48 (1992) 965–969; doi:10.1107/S0108270192000921

data_2000937
_publ_section_title
;Unusual conformation of
 (<i>R</i>,<i>R</i>)-<i>N</i>,<i>N</i>,<i>N</i>',<i>N</i>'-tetramethyltartramide
 (I) and its <i>O</i>,<i>O</i>'-dibenzoyl derivative (II)
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              965
_journal_page_last               969
_journal_paper_doi               10.1107/S0108270192000921
_journal_volume                  48
_journal_year                    1992
_chemical_formula_sum            'C22 H24 N2 O6'
_chemical_formula_weight         412.44
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_cell_angle_alpha                90
_cell_angle_beta                 102.783(9)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   9.5780(10)
_cell_length_b                   13.6920(10)
_cell_length_c                   8.5080(10)
_cell_measurement_reflns_used    15
_cell_measurement_temperature    295
_cell_measurement_theta_max      16.1
_cell_measurement_theta_min      8.0
_cell_volume                     1088.10(19)
_diffrn_measurement_device       'Syntex P2~1~'
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.024
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            2941
_diffrn_reflns_theta_max         58
_diffrn_standards_decay_%        .0
_diffrn_standards_interval_time  100
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.73
_exptl_crystal_colour            Transparent
_exptl_crystal_density_diffrn    1.26
_exptl_crystal_density_meas      1.26
_exptl_crystal_description       Needle
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.35
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.19
_refine_diff_density_min         -0.18
_refine_ls_extinction_coef       1.37(1)x10^-5^
_refine_ls_extinction_method     F^*^~c~=F~c~(1-xF^2^~c~/sin\q)
_refine_ls_goodness_of_fit_obs   3.4
_refine_ls_hydrogen_treatment    refU
_refine_ls_number_parameters     280
_refine_ls_number_reflns         2795
_refine_ls_R_factor_obs          0.036
_refine_ls_shift/esd_max         0.16
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/(\s^2^~F~+0.0001F^2^)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.050
_reflns_number_observed          2810
_reflns_number_total             2906
_reflns_observed_criterion       I>=1.96\s(I)
_cod_data_source_file            ab1002.cif
_cod_data_source_block           ab1002b
_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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/(\s^2^~F~+0.0001F^2^)' 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^~F~+0.0001F^2^)'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1088.1(2)
_cod_database_code               2000937