H-Bond Breaking in High-Pressure Urea
Olejniczak, Anna; Ostrowska, Kinga; Katrusiak, Andrzej; The Journal of Physical Chemistry C 113 (2009) 15761–; doi:10.1021/jp904942c

data_1544224
_publ_contact_author_address
;Faculty of Chemistry,
Adam Mickiewicz University,
Grunwaldzka 6, 60-780 Poznan
Poland
;
_publ_contact_author_email       katran@amu.edu.pl
_publ_contact_author_fax         +48(61)8658008
_publ_contact_author_name        'Andrzej Katrusiak'
_publ_contact_author_phone       +48(61)8291443
_publ_section_title
;
 H-Bond Breaking in High-Pressure Urea
;
_journal_issue                   35
_journal_name_full               'The Journal of Physical Chemistry C'
_journal_page_first              15761
_journal_paper_doi               10.1021/jp904942c
_journal_volume                  113
_journal_year                    2009
_chemical_formula_moiety         'C H4 N2 O'
_chemical_formula_sum            'C H4 N2 O'
_chemical_formula_weight         60.06
_chemical_melting_point          405
_chemical_name_common            urea
_chemical_name_systematic
; 
urea
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 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            4
_cell_length_a                   3.6235(11)
_cell_length_b                   8.272(4)
_cell_length_c                   8.844(4)
_cell_measurement_pressure       800000
_cell_measurement_reflns_used    271
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      29.36
_cell_measurement_theta_min      3.37
_cell_volume                     265.09(19)
_computing_cell_refinement       'CrysAlis (Oxford Diffraction, 2002)'
_computing_data_collection       'CrysAlis (Oxford Diffraction, 2002)'
_computing_data_reduction        'CrysAlis (Oxford Diffraction, 2002)'
_computing_molecular_graphics
;X-Seed (Barbour, 2001) 
and POV-Ray (Persistence of Vision, 2004)
;
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_detector_area_resol_mean 16.4
_diffrn_measured_fraction_theta_full 0.357
_diffrn_measured_fraction_theta_max 0.357
_diffrn_measurement_device_type  'Kuma KM4CCD \k geometry'
_diffrn_measurement_method
;HP omega scans - for more details see:
A. Budzianowski, A. Katrusiak in High-Pressure Crystallography
(Eds.: A. Katrusiak, P. F. McMillan),
Dordrecht: Kluwer Acad. Publ., 2004 pp.157-168
;
_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  0.0819
_diffrn_reflns_av_sigmaI/netI    0.0380
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            1790
_diffrn_reflns_theta_full        29.36
_diffrn_reflns_theta_max         29.36
_diffrn_reflns_theta_min         3.37
_exptl_absorpt_coefficient_mu    0.129
_exptl_absorpt_correction_T_max  0.92
_exptl_absorpt_correction_T_min  0.49
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details
;
Katrusiak, A. (2003). REDSHABS - Program for correcting
reflections intensities for DAC absorption, gasket shadowing
and sample crystal absorption. Adam Mickiewicz University, Pozna\'n.
Katrusiak, A. (2004). Z. Kristallogr. 219, 461-467
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.505
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             128
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.43
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.153
_refine_diff_density_min         -0.135
_refine_diff_density_rms         0.039
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1(5)
_refine_ls_extinction_coef       0.31(9)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.187
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     38
_refine_ls_number_reflns         271
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.187
_refine_ls_R_factor_all          0.0579
_refine_ls_R_factor_gt           0.0538
_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^)+(0.0582P)^2^+0.0827P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1194
_refine_ls_wR_factor_ref         0.1215
_reflns_number_gt                251
_reflns_number_total             271
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            urea.cif
_cod_data_source_block           urea_080
_cod_original_cell_volume        265.09(18)
_cod_database_code               1544224