<small>L</small>-Histidinium trichloroacetate
S. Gokul Raj; G. Ramesh Kumar; R. Mohan; R. Jayavel; Babu Varghese; Acta Crystallographica Section E 62 (2006) o1704–o1706; doi:10.1107/S1600536806011342

data_2209036
_publ_section_title
;
 <small>L</small>-Histidinium trichloroacetate
;
_journal_coeditor_code           WN2004
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1704
_journal_page_last               o1706
_journal_paper_doi               10.1107/S1600536806011342
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C6 H10 N3 O2 +, C2 Cl3 O2 -'
_chemical_formula_moiety         'C6 H10 N3 O2 +, C2 Cl3 O2 -'
_chemical_formula_sum            'C8 H10 Cl3 N3 O4'
_chemical_formula_weight         318.54
_chemical_name_common            'L-histidinium trichloroacetate'
_chemical_name_systematic
;
L-histidinium trichloroacetate
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_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                 99.98(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.4505(18)
_cell_length_b                   25.769(8)
_cell_length_c                   9.210(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      14
_cell_measurement_theta_min      10
_cell_volume                     1274.0(6)
_computing_cell_refinement       'CAD-4 Software'
_computing_data_collection       'CAD-4 Software (Enraf--Nonius, 1988)'
_computing_data_reduction
;
XCAD4 (Harms & Wocadlo, 1995) in WinGX (Farrugia, 1999)
;
_computing_molecular_graphics    'ORTEP32 (Farrugia, 1997)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution
;
SIR92 (Altomare <i>et al.</i>,  1993) in WinGX
;
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Enraf--Nonius CAD-4'
_diffrn_measurement_method       \w-2\q
_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  0.0220
_diffrn_reflns_av_sigmaI/netI    0.0163
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       30
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            2539
_diffrn_reflns_theta_full        24.98
_diffrn_reflns_theta_max         24.98
_diffrn_reflns_theta_min         2.25
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  60
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    0.729
_exptl_absorpt_correction_T_max  0.9992
_exptl_absorpt_correction_T_min  0.8789
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(North <i>et al.</i>,  1968)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.661
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'cut from a needle'
_exptl_crystal_F_000             648
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.362
_refine_diff_density_min         -0.285
_refine_ls_abs_structure_details 'Flack (1983), 253 Friedel pairs'
_refine_ls_abs_structure_Flack   0.21(11)
_refine_ls_extinction_coef       0.080(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.064
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     427
_refine_ls_number_reflns         2300
_refine_ls_number_restraints     263
_refine_ls_restrained_S_all      1.181
_refine_ls_R_factor_all          0.0426
_refine_ls_R_factor_gt           0.0390
_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^)+(0.0685P)^2^+0.5935P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1048
_refine_ls_wR_factor_ref         0.1089
_reflns_number_gt                2155
_reflns_number_total             2300
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            wn2004.cif
_cod_data_source_block           I
_cod_original_cell_volume        1274.0(7)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               2209036