Molecular structure of clonidine: gas-phase electron diffraction, single-crystal X-ray diffraction and quantum chemical studies.
Kolesnikova, Inna N.; Rykov, Anatolii N.; Shishkov, Igor F.; Tafeenko, Victor A.; Aslanov, Leonid A.; Physical chemistry chemical physics : PCCP 19 (2017) 4618–4626; doi:10.1039/c6cp08401j

data_7227366
_publ_section_title
;
 Molecular structure of clonidine: gas-phase electron diffraction,
 single-crystal X-ray diffraction and quantum chemical studies.
;
_journal_issue                   6
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              4618
_journal_page_last               4626
_journal_paper_doi               10.1039/c6cp08401j
_journal_volume                  19
_journal_year                    2017
_chemical_formula_moiety         'C9 H9 Cl2 N3'
_chemical_formula_sum            'C9 H9 Cl2 N3'
_chemical_formula_weight         230.09
_chemical_name_common            Clonidine
_chemical_name_systematic        2-(2,6-dichlorophenylamino)-2-imidazoline
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2016-12-07 deposited with the CCDC.
2017-01-05 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 115.0720(10)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   17.84330(10)
_cell_length_b                   8.2767(3)
_cell_length_c                   15.1223(6)
_cell_measurement_reflns_used    1687
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      65.5
_cell_measurement_theta_min      2.3
_cell_volume                     2022.88(11)
_computing_cell_refinement       'STOE X-AREA'
_computing_data_collection       'STOE X-AREA'
_computing_data_reduction        'STOE X-RED'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      295
_diffrn_detector                 Pilatus100K
_diffrn_detector_area_resol_mean 5.81
_diffrn_detector_type            STOE
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  STOE
_diffrn_measurement_method       'rotation method'
_diffrn_radiation_collimation    'focusing mirrors'
_diffrn_radiation_monochromator  none
_diffrn_radiation_polarisn_norm  0
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54186
_diffrn_reflns_av_R_equivalents  0.0490
_diffrn_reflns_av_unetI/netI     0.0476
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            15511
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        67.686
_diffrn_reflns_theta_max         72.765
_diffrn_reflns_theta_min         5.040
_diffrn_source                   'Cu GeniX 3D'
_diffrn_source_current           0.600
_diffrn_source_power             0.030
_diffrn_source_voltage           50
_exptl_absorpt_coefficient_mu    5.463
_exptl_absorpt_correction_T_max  0.4430
_exptl_absorpt_correction_T_min  0.3881
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
[c.f. r.h. blessing, acta cryst. (1995), a51, 33-38]
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.511
_exptl_crystal_description       block
_exptl_crystal_F_000             944
_exptl_crystal_size_max          .25
_exptl_crystal_size_mid          .16
_exptl_crystal_size_min          .1
_refine_diff_density_max         0.300
_refine_diff_density_min         -0.243
_refine_diff_density_rms         0.053
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.894
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     278
_refine_ls_number_reflns         3994
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      0.894
_refine_ls_R_factor_all          0.0718
_refine_ls_R_factor_gt           0.0402
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0579P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0937
_refine_ls_wR_factor_ref         0.1089
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2449
_reflns_number_total             3994
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c6cp08401j2.cif
_cod_data_source_block           clonidine
_cod_depositor_comments          'Adding full bibliography for 7227366.cif.'
_cod_database_code               7227366
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              3699
_shelx_hkl_checksum              92728