Mechanism of the first-order phase transition of an acylurea derivative: observation of intermediate stages of transformation with a detailed temperature-resolved single-crystal diffraction method
Hashizume, Daisuke; Miki, Naoko; Yamazaki, Toshiyuki; Aoyagi, Yosuke; Arisato, Tomokuni; Uchiyama, Hiroki; Endo, Tadashi; Yasui, Masanori; Iwasaki, Fujiko; Acta Crystallographica Section B 59 (2003) 404–415; doi:10.1107/S0108768103005792

data_2103902
_publ_section_title
;
 Mechanism of the first-order phase transition of an acylurea
 derivative: observation of intermediate stages of transformation with
 a detailed temperature-resolved single-crystal diffraction method
;
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              404
_journal_page_last               415
_journal_paper_doi               10.1107/S0108768103005792
_journal_volume                  59
_journal_year                    2003
_chemical_formula_moiety         'C9 H18 N2 O2'
_chemical_formula_sum            'C9 H18 N2 O2'
_chemical_formula_weight         186.25
_chemical_melting_point          375
_chemical_name_systematic
;
 1-ethyl-3-(4-methylpentanoyl)urea
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                85.948(12)
_cell_angle_beta                 91.71(2)
_cell_angle_gamma                88.030(13)
_cell_formula_units_Z            2
_cell_length_a                   8.6337(14)
_cell_length_b                   13.1782(16)
_cell_length_c                   5.2242(18)
_cell_measurement_reflns_used    1921
_cell_measurement_temperature    374
_cell_measurement_theta_max      27.435
_cell_measurement_theta_min      1.55
_cell_volume                     592.2(2)
_computing_cell_refinement       'PROCESS-AUTO (Rigaku Corporation, 1998)'
_computing_data_collection       'PROCESS-AUTO (Rigaku Corporation, 1998)'
_computing_data_reduction        'PROCESS-AUTO (Rigaku Corporation, 1998)'
_computing_molecular_graphics    'ORTEP-III (Burnett & Johnson, 1996)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution
;
 The final structure at 372K was used as an initial model.
 The minor part of the disordered 3-methylbutyl group was
 deleted to avoid some viases for disorder analysis.
;
_diffrn_ambient_temperature      374
_diffrn_detector_area_resol_mean 10
_diffrn_measured_fraction_theta_full 0.724
_diffrn_measured_fraction_theta_max 0.724
_diffrn_measurement_device       'RIGAKU RAXIS-RAPID'
_diffrn_measurement_method       'Oscillation method'
_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  0.041
_diffrn_reflns_av_sigmaI/netI    0.0369
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            8267
_diffrn_reflns_theta_full        27.47
_diffrn_reflns_theta_max         27.47
_diffrn_reflns_theta_min         2.36
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.074
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.044
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             204
_exptl_crystal_size_max          1.00
_exptl_crystal_size_mid          0.60
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.220
_refine_diff_density_min         -0.222
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.846
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     131
_refine_ls_number_reflns         1962
_refine_ls_number_restraints     17
_refine_ls_restrained_S_all      1.846
_refine_ls_R_factor_all          0.2397
_refine_ls_R_factor_gt           0.1519
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.3442
_refine_ls_wR_factor_ref         0.3786
_reflns_number_gt                826
_reflns_number_total             1962
_reflns_threshold_expression     >2\s(I)
_cod_data_source_file            lc0061.cif
_cod_data_source_block           ethyl374K
_cod_database_code               2103902
_cod_database_fobs_code          2103902