#------------------------------------------------------------------------------
#$Date: 2025-08-23 02:36:08 +0300 (Sat, 23 Aug 2025) $
#$Revision: 301880 $
#$URL: file:///home/coder/svn-repositories/cod/cif/8/00/03/8000342.cif $
#------------------------------------------------------------------------------
#
# This file is available in the Crystallography Open Database (COD),
# http://www.crystallography.net/
#
# All data on this site have been placed in the public domain by the
# contributors.
#
data_8000342
loop_
_publ_author_name
'Sarkar, Sounak'
'Thomas, Sajesh P.'
'Potnuru, Lokeswara Rao'
'Edwards, Alison J.'
'Grosjean, Arnaud'
'Ramanathan, Krishna Venkatachala'
'Guru Row, T. N.'
_publ_section_title
;
 Experimental Insights into the Electronic Nature, Spectral Features, and
 Role of Entropy in Short
 CH₃···CH₃ Hydrophobic
 Interactions.
;
_journal_issue                   22
_journal_name_full               'The journal of physical chemistry letters'
_journal_page_first              7224
_journal_page_last               7229
_journal_paper_doi               10.1021/acs.jpclett.9b02734
_journal_volume                  10
_journal_year                    2019
_chemical_formula_moiety         'C6 H12 N2, C4 H2 O4'
_chemical_formula_sum            'C10 H14 N2 O4'
_chemical_formula_weight         226.23
_chemical_name_common            '2,3,5,6-tetramethylpyrazine:oxalic acid'
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   difmap
_audit_creation_method           SHELXL-2018/3
_cell_angle_alpha                81.922(3)
_cell_angle_beta                 80.362(3)
_cell_angle_gamma                85.796(3)
_cell_formula_units_Z            1
_cell_length_a                   3.80841(13)
_cell_length_b                   8.3454(3)
_cell_length_c                   8.5998(3)
_cell_measurement_reflns_used    5300
_cell_measurement_temperature    100.00(2)
_cell_measurement_theta_max      36.2490
_cell_measurement_theta_min      2.3940
_cell_volume                     266.446(16)
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      100.00(2)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 8.0419
_diffrn_detector_type            Eos
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Eos, Nova'
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0260
_diffrn_reflns_av_unetI/netI     0.0351
_diffrn_reflns_Laue_measured_fraction_full 0.996
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_number            2589
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         36.307
_diffrn_reflns_theta_min         2.423
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'Mova (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    0.110
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.410
_exptl_crystal_description       block
_exptl_crystal_F_000             120
_refine_diff_density_max         0.596
_refine_diff_density_min         -0.232
_refine_diff_density_rms         0.056
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.065
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     101
_refine_ls_number_reflns         2589
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.065
_refine_ls_R_factor_all          0.0407
_refine_ls_R_factor_gt           0.0359
_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/[σ²(Fo²)+(0.0550P)²+0.0460P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1064
_refine_ls_wR_factor_ref         0.1097
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2302
_reflns_number_total             2589
_reflns_threshold_expression     'I > 2σ(I)'
_cod_data_source_file            jz9b02734_si_003.cif
_cod_data_source_block           TMP-OA-100K
_cod_depositor_comments
'Adding full bibliography for 8000326--8000347.cif.'
_cod_original_cell_volume        266.446(17)
_cod_database_code               8000342
_shelx_shelxl_version_number     2018/3
_shelx_space_group_comment
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x, -y, -z'
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_site_symmetry_order
_atom_site_calc_flag
O2 O 0.41998(15) 0.80126(6) 0.08829(6) 0.01658(11) Uani 1 1 d
O1 O 0.63780(18) 1.00473(7) 0.18325(6) 0.02247(13) Uani 1 1 d
N1 N 0.46415(13) 0.60354(6) 0.36338(6) 0.00985(10) Uani 1 1 d
C4 C 0.64365(15) 0.45969(7) 0.35446(6) 0.00933(10) Uani 1 1 d
C2 C 0.31937(15) 0.64561(7) 0.50636(6) 0.00939(10) Uani 1 1 d
C5 C 0.79842(18) 0.41660(8) 0.19272(7) 0.01414(12) Uani 1 1 d
H5A H 0.725(4) 0.3147(16) 0.1740(15) 0.024(3) Uiso 1 1 d
H5B H 1.053(4) 0.4059(16) 0.1794(17) 0.032(3) Uiso 1 1 d
H5C H 0.728(4) 0.5008(16) 0.1107(16) 0.029(3) Uiso 1 1 d
C3 C 0.12661(18) 0.80796(7) 0.51120(8) 0.01394(12) Uani 1 1 d
H3A H 0.039(4) 0.8430(17) 0.4114(17) 0.034(3) Uiso 1 1 d
H3B H 0.272(4) 0.8834(18) 0.5350(18) 0.038(4) Uiso 1 1 d
H3C H -0.079(3) 0.8034(15) 0.5934(14) 0.025(3) Uiso 1 1 d
C1 C 0.52225(18) 0.94955(7) 0.08055(7) 0.01364(12) Uani 1 1 d
H2 H 0.438(5) 0.744(2) 0.184(2) 0.046(4) Uiso 1 1 d
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
C1 O2 H2 111.3(10) . .
C4 N1 C2 119.57(5) . .
N1 C4 C2 120.14(5) . 2_666
N1 C4 C5 117.96(5) . .
C2 C4 C5 121.90(5) 2_666 .
N1 C2 C4 120.29(5) . 2_666
N1 C2 C3 117.87(5) . .
C4 C2 C3 121.83(5) 2_666 .
C4 C5 H5A 112.9(8) . .
C4 C5 H5B 111.3(9) . .
H5A C5 H5B 105.3(11) . .
C4 C5 H5C 109.9(8) . .
H5A C5 H5C 108.5(11) . .
H5B C5 H5C 108.8(11) . .
C2 C3 H3A 110.1(8) . .
C2 C3 H3B 110.9(10) . .
H3A C3 H3B 112.0(12) . .
C2 C3 H3C 111.2(7) . .
H3A C3 H3C 106.4(11) . .
H3B C3 H3C 106.2(12) . .
O1 C1 O2 126.19(6) . .
O1 C1 C1 122.43(7) . 2_675
O2 C1 C1 111.37(6) . 2_675
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
O2 C1 1.3140(8) .
O2 H2 0.904(16) .
O1 C1 1.2083(8) .
N1 C4 1.3426(7) .
N1 C2 1.3435(7) .
C4 C2 1.4027(8) 2_666
C4 C5 1.4988(8) .
C2 C3 1.4954(8) .
C5 H5A 0.957(13) .
C5 H5B 0.956(14) .
C5 H5C 0.980(13) .
C3 H3A 0.972(15) .
C3 H3B 0.934(15) .
C3 H3C 0.962(13) .
C1 C1 1.5450(12) 2_675
loop_
_cod_related_entry_id
_cod_related_entry_database
_cod_related_entry_code
1 PubChem 139146850
