Supramolecular architectures in the reaction products of caffeine with dihalogens: crystal structures of the CT-adduct bis(caffeine)-diiodine and the caffeinium iodine dichloride salt
Isaia, Francesco; Aragoni, Maria Carla; Arca, Massimiliano; Demartin, Francesco; Garau, Alessandra; Lippolis, Vito; Pivetta, Tiziana; Podda, Enrico; New Journal of Chemistry 50 (2026) 5253–5265; doi:10.1039/D5NJ05002B

data_7064294
_publ_section_title
;
 Supramolecular architectures in the reaction products of caffeine with
 dihalogens: crystal structures of the CT-adduct bis(caffeine)-diiodine
 and the caffeinium iodine dichloride salt
;
_journal_issue                   12
_journal_name_full               'New Journal of Chemistry'
_journal_page_first              5253
_journal_page_last               5265
_journal_paper_doi               10.1039/D5NJ05002B
_journal_volume                  50
_journal_year                    2026
_chemical_formula_sum            'C8 H11 Cl2 I N4 O2'
_chemical_formula_weight         393.01
_chemical_name_common            'caffeinium iodine dichloride'
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_audit_creation_method           SHELXL-2017/1
_audit_update_record
;
2025-11-11 deposited with the CCDC.	2026-02-20 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 91.77(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.770(3)
_cell_length_b                   10.790(2)
_cell_length_c                   14.274(7)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      13.03
_cell_measurement_theta_min      7.28
_cell_volume                     1350.1(8)
_computing_cell_refinement       'Enraf Nonius CAD4 software'
_computing_data_collection       'Enraf Nonius CAD4 software'
_computing_data_reduction
'SDP package of crystallographic programs. B. Frenz'
_computing_structure_refinement  'SHELXL-2017/1 (Sheldrick, 2017)'
_computing_structure_solution    SIR92
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Enraf Nonius CAD4 diffractometer'
_diffrn_measurement_method       'omega scan'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_unetI/netI     0.0389
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            2372
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        24.964
_diffrn_reflns_theta_max         24.964
_diffrn_reflns_theta_min         3.286
_exptl_absorpt_coefficient_mu    2.764
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details
'A.C.T. North,D.C Phillips,F.S.Mathews,Acta Crystallogr A 1968, 24, 351-359'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.934
_exptl_crystal_description       prism
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.08
_exptl_transmission_factor_max   1.000
_exptl_transmission_factor_min   0.810
_refine_diff_density_max         0.613
_refine_diff_density_min         -1.727
_refine_diff_density_rms         0.131
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.033
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     154
_refine_ls_number_reflns         2372
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0824
_refine_ls_R_factor_gt           0.0548
_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^)+(0.0938P)^2^+0.9846P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1403
_refine_ls_wR_factor_ref         0.1586
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1678
_reflns_number_total             2372
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5nj05002b2.cif
_cod_data_source_block           hcaf_icl2
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_exptl_absorpt_correction_type' value 'Psi-scan' was
changed to 'psi-scan' in accordance with the
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/RSC/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

Automatic conversion script
Id: cif_fix_values 8170 2020-07-09 18:12:32Z antanas 

 Adding full bibliography for 7064293--7064294.cif.
;
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               7064294
_shelx_shelxl_version_number     2017/1
_shelx_res_checksum              7921