Exploration of plastic-like phases in alkylurea systems. A thermal and X-ray study
Hashimoto, Masao; Tajima, Fukue; Eda, Kazuo; Yamamura, Kimiaki; Okazaki, Tadashi; Journal of Molecular Structure 734 (2005) 23–33; doi:10.1016/j.molstruc.2004.08.008

data_1100996
_publ_section_title
;
 Exploration of plastic-like phases in alkylurea systems.
 A thermal and X-ray study
;
_journal_issue                   1-3
_journal_name_full               'Journal of Molecular Structure'
_journal_page_first              23
_journal_page_last               33
_journal_paper_doi               10.1016/j.molstruc.2004.08.008
_journal_volume                  734
_journal_year                    2005
_chemical_formula_moiety         'C7 H16 N2 O'
_chemical_formula_sum            'C7 H16 N2 O'
_chemical_formula_weight         144.22
_chemical_melting_point          383.0
_chemical_name_common            n-hexylurea
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 92.730(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.976(3)
_cell_length_b                   7.4298(16)
_cell_length_c                   9.287(2)
_cell_measurement_reflns_used    1509
_cell_measurement_temperature    297(2)
_cell_measurement_theta_max      24.889
_cell_measurement_theta_min      3.144
_cell_volume                     894.4(3)
_diffrn_ambient_temperature      297(2)
_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  0.0353
_diffrn_reflns_av_sigmaI/netI    0.0364
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            4932
_diffrn_reflns_theta_max         27.31
_diffrn_reflns_theta_min         3.14
_exptl_absorpt_coefficient_mu    0.073
_exptl_absorpt_correction_T_max  1.000000
_exptl_absorpt_correction_T_min  0.717185
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'program SADABS ver. 2.03(Sheldrick)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.071
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             320
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.34
_exptl_crystal_size_min          0.20
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.897
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     155
_refine_ls_number_reflns         1805
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.897
_refine_ls_R_factor_all          0.0890
_refine_ls_R_factor_gt           0.0529
_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^)+(0.0930P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1273
_refine_ls_wR_factor_ref         0.1424
_reflns_number_gt                1057
_reflns_number_total             1805
_reflns_threshold_expression     >2sigma(I)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               1100996