New polymorphs of curcumin
Palash Sanphui; N. Rajesh Goud; U. B. Rao Khandavilli; Sreenu Bhanoth; Ashwini Nangia; Chem.Commun. 47 (2011) 5013–; doi:10.1039/c1cc10204d

data_7106287
_publ_section_title
;
 New polymorphs of curcumin
;
_journal_name_full               Chem.Commun.
_journal_page_first              5013
_journal_paper_doi               10.1039/c1cc10204d
_journal_volume                  47
_journal_year                    2011
_chemical_formula_sum            'C21 H20 O6'
_chemical_formula_weight         368.37
_chemical_name_systematic
;
?
;
_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            8
_cell_length_a                   35.417(3)
_cell_length_b                   7.7792(7)
_cell_length_c                   12.6482(11)
_cell_measurement_reflns_used    6973
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      25.89
_cell_measurement_theta_min      2.30
_cell_volume                     3484.8(5)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0497
_diffrn_reflns_av_sigmaI/netI    0.0385
_diffrn_reflns_limit_h_max       43
_diffrn_reflns_limit_h_min       -43
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            34779
_diffrn_reflns_theta_full        26.02
_diffrn_reflns_theta_max         26.02
_diffrn_reflns_theta_min         1.15
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9817
_exptl_absorpt_correction_T_min  0.9697
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   Sadabs
_exptl_crystal_colour            'Dark Yellow'
_exptl_crystal_density_diffrn    1.404
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Block
_exptl_crystal_F_000             1552
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.583
_refine_diff_density_min         -0.221
_refine_diff_density_rms         0.057
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.4(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.070
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     515
_refine_ls_number_reflns         6854
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      1.070
_refine_ls_R_factor_all          0.0584
_refine_ls_R_factor_gt           0.0524
_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^)+(0.0663P)^2^+1.1128P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1216
_refine_ls_wR_factor_ref         0.1249
_reflns_number_gt                6199
_reflns_number_total             6854
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c1cc10204d.txt
_cod_data_source_block           Form2_Pca21
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_absorpt_correction_type' value 'Multi-scan' changed to
'multi-scan' according to the built-in table from CIF Core dictionary
named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
;
_cod_original_cell_volume        3484.7(5)
_cod_original_sg_symbol_H-M      'Pca2(1) '
_cod_database_code               7106287