Methylxanthines. I. Anhydrous Theophylline
Ebisuzaki, Yukiko; Boyle, Paul D.; Smith, Jennifer A.; Acta Crystallographica Section C 53 (1997) 777–779; doi:10.1107/S0108270197001960

data_2006182
_publ_section_title
;
 Methylxanthines. I. Anhydrous Theophylline
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              777
_journal_page_last               779
_journal_paper_doi               10.1107/S0108270197001960
_journal_volume                  53
_journal_year                    1997
_chemical_formula_moiety         'C7 H8 N4 O2'
_chemical_formula_sum            'C7 H8 N4 O2'
_chemical_formula_weight         180.16
_chemical_name_common            Theophylline
_chemical_name_systematic
;
 3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione
;
_space_group_IT_number           33
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_cell_angle_alpha                90.0
_cell_angle_beta                 90.0
_cell_angle_gamma                90.0
_cell_formula_units_Z            4
_cell_length_a                   24.612(2)
_cell_length_b                   3.8302(4)
_cell_length_c                   8.5010(5)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293
_cell_measurement_theta_max      20.00
_cell_measurement_theta_min      12.00
_cell_volume                     801.38(12)
_computing_data_reduction
'NRCVAX DATRD2 (Gabe, Le Page, Charland, Lee & White, 1989)'
_computing_molecular_graphics    'NRCVAX, ORTEPII (Johnson, 1976)'
_computing_publication_material  'NRCVAX TABLES Jan 94 Version'
_computing_structure_refinement  'NRCVAX LSTSQ'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Nonius CAD-4'
_diffrn_measurement_method       '\w scan b/P/b'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'xray tube'
_diffrn_radiation_type           'Molybdenum K\a'
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .000
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            752
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         0.00
_diffrn_standards_decay_%        '< 1'
_diffrn_standards_interval_time  80
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    .11
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  1.0000
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.493
_exptl_crystal_density_meas      ?
_exptl_crystal_description       'thin plate'
_exptl_crystal_F_000             376.18
_exptl_crystal_size_max          .45
_exptl_crystal_size_mid          .30
_exptl_crystal_size_min          .03
_refine_diff_density_max         .25
_refine_diff_density_min         -.23
_refine_ls_extinction_coef       '4.2(14) x 10'
_refine_ls_extinction_method     'Larson (1970)'
_refine_ls_goodness_of_fit_obs   1.65
_refine_ls_hydrogen_treatment    'see text for treatment of hydrogens'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     126
_refine_ls_number_reflns         646
_refine_ls_R_factor_all          .053
_refine_ls_R_factor_obs          .053
_refine_ls_shift/esd_max         .001
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1/[\s^2^(F)+ 0.0005F^2^]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         .056
_refine_ls_wR_factor_obs         .056
_reflns_number_observed          646
_reflns_number_total             752
_reflns_observed_criterion       'Inet >  0.5\s(Inet)'
_cod_data_source_file            bk1284.cif
_cod_data_source_block           Theopylline
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
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:

'_atom_site_thermal_displace_type' tag value 'Uij' was replaced with
'Uani' value 13 times.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' 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:

'_exptl_crystal_density_meas' value 'not measured' 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 '1/[\s^2^(F)+ 0.0005F^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)+
0.0005F^2^]'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               2006182