A crystallographic titration of the dipeptide <small>L</small>-isoleucyl-<small>L</small>-isoleucine
Görbitz, Carl Henrik; Acta Crystallographica Section B 60 (2004) 569–577; doi:10.1107/S0108768104014569

data_2102618
_publ_section_title
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 A crystallographic titration of the dipeptide
 <small>L</small>-isoleucyl-<small>L</small>-isoleucine
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              569
_journal_page_last               577
_journal_paper_doi               10.1107/S0108768104014569
_journal_volume                  60
_journal_year                    2004
_chemical_formula_sum            'C12 H27 N3 O3'
_chemical_formula_weight         261.37
_chemical_name_systematic
;
  Ammonium L-Leucyl-L-Leucinate
;
_space_group_IT_number           1
_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                81.580(3)
_cell_angle_beta                 80.484(3)
_cell_angle_gamma                88.350(3)
_cell_formula_units_Z            2
_cell_length_a                   6.7765(15)
_cell_length_b                   9.718(2)
_cell_length_c                   11.882(3)
_cell_measurement_reflns_used    2001
_cell_measurement_temperature    105(2)
_cell_measurement_theta_max      26.37
_cell_measurement_theta_min      2.12
_cell_volume                     763.4(3)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 1998)'
_computing_data_reduction        'SAINT (Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL (Bruker, 2000)'
_computing_publication_material  'SHELXTL (Bruker, 2000)'
_computing_structure_refinement  'SHELXTL (Bruker, 2000)'
_computing_structure_solution    'SHELXTL (Bruker, 2000)'
_diffrn_ambient_temperature      105(2)
_diffrn_detector_area_resol_mean 8.3
_diffrn_measured_fraction_theta_full 0.979
_diffrn_measured_fraction_theta_max 0.979
_diffrn_measurement_device_type  'Siemens SMART CCD diffractometer'
_diffrn_measurement_method
'Sets of exposures each taken over 0.3\% \w rotation'
_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  0.0446
_diffrn_reflns_av_sigmaI/netI    0.0761
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            6449
_diffrn_reflns_theta_full        26.37
_diffrn_reflns_theta_max         26.37
_diffrn_reflns_theta_min         2.12
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_T_max  0.982
_exptl_absorpt_correction_T_min  0.779
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.137
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       Block
_exptl_crystal_F_000             288
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.319
_refine_diff_density_min         -0.234
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.7(14)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.983
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     395
_refine_ls_number_reflns         3063
_refine_ls_number_restraints     11
_refine_ls_restrained_S_all      0.983
_refine_ls_R_factor_all          0.0830
_refine_ls_R_factor_gt           0.0443
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0564P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0928
_refine_ls_wR_factor_ref         0.1080
_reflns_number_gt                2165
_reflns_number_total             3063
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            de5006.cif
_cod_data_source_block           IIa
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_database_code               2102618