Pressure-induced isosymmetric phase transition in biurea
Bull, Craig L.; Funnell, Nicholas P.; Ridley, Christopher J.; Pulham, Colin R.; Coster, Paul L.; Tellam, James P.; Marshall, William G.; CrystEngComm 21 (2019) 5872–; doi:10.1039/C9CE01028A

data_7233459
_publ_section_title
;
 Pressure-induced isosymmetric phase transition in biurea
;
_journal_issue                   39
_journal_name_full               CrystEngComm
_journal_page_first              5872
_journal_paper_doi               10.1039/C9CE01028A
_journal_volume                  21
_journal_year                    2019
_chemical_compound_source        'Sigma Aldrich'
_chemical_formula_moiety         'C2 D6 N4 O2'
_chemical_formula_sum            'C D3 N2 O'
_chemical_formula_weight         62.07
_chemical_melting_point          531
_chemical_name_common            Biurea
_space_group_IT_number           15
_space_group_name_Hall           '-I 2ya'
_space_group_name_H-M_alt        'I 1 2/a 1'
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      15
_symmetry_space_group_name_Hall  '-I 2ya'
_symmetry_space_group_name_H-M   'I 1 2/a 1'
_audit_update_record
;
2019-06-21 deposited with the CCDC.    2019-08-26 downloaded from the CCDC.
;
_cell_angle_alpha                90.0
_cell_angle_beta                 77.346(4)
_cell_angle_gamma                90.0
_cell_formula_units_Z            8
_cell_length_a                   9.4568(4)
_cell_length_b                   3.51779(9)
_cell_length_c                   13.1178(6)
_cell_measurement_pressure       1.87
_cell_measurement_temperature    295
_cell_volume                     425.79(3)
_computing_cell_refinement       GSAS
_computing_data_collection       'Custom ISIS software'
_diffrn_ambient_temperature      295
_diffrn_detector                 'ZnS scintillator'
_diffrn_detector_type            custom
_diffrn_measurement_device_type  'PEARL diffractometer'
_diffrn_radiation_monochromator  none
_diffrn_radiation_type           Neutron
_diffrn_source                   'Pulsed neutron source'
_diffrn_source_target            W
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
Calculated using custom ISIS routines.
;
_pd_char_colour                  white
_pd_instr_dist_spec/detc         800
_pd_instr_dist_src/spec          12800
_pd_instr_location
'ISIS Neutron Facility, Rutherford Appleton Laboratory'
_pd_meas_2theta_fixed            90
_pd_meas_scan_method             Time-of-flight
_pd_proc_info_data_reduction
;
Custom ISIS software
;
_pd_proc_info_excluded_regions
;

;
_pd_proc_ls_background_function  'Chebychev polynomial'
_pd_proc_ls_pref_orient_corr
;
No requirement for preferred orientation correction
;
_pd_proc_ls_profile_function
;
Voigt function convoluted with a back-to-back double exponential.
;
_pd_proc_ls_prof_wR_factor       0.0256
_pd_spec_mounting                'TiZr Capsule'
_pd_spec_mount_mode              transmission
_refine_ls_goodness_of_fit_all   1.824
_refine_ls_hydrogen_treatment    refxyz
_refine_ls_matrix_type           full
_refine_ls_number_constraints    2
_refine_ls_number_parameters     64
_refine_ls_number_restraints     0
_refine_ls_R_Fsqd_factor         0.0863
_refine_ls_shift/su_max          0.02
_refine_ls_weighting_scheme      sigma
_cod_data_source_file            c9ce01028a2.cif
_cod_data_source_block           PRL87942_45_18TNS_publ
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '531 K' was changed to '531' - the
value should be numeric and without a unit designator.

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

'_geom_bond_publ_flag' value 'N' changed to 'n' according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (35
times).

'_geom_angle_publ_flag' value 'N' changed to 'n' according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26 (9
times).

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 

 Adding full bibliography for 7233455--7233473.cif.
;
_cod_original_cell_volume        425.788(20)
_cod_original_sg_symbol_H-M      'I 2/a'
_cod_database_code               7233459