Inversion of the melting point alternation in n-alkyl carboxylic acids by co-crystallization with pyrazine
Bond, Andrew D.; CrystEngComm 8 (2006) 333–; doi:10.1039/b517513e

data_7203242
_publ_section_title
;
 Inversion of the melting point alternation in n-alkyl carboxylic acids
 by co-crystallization with pyrazine
;
_journal_issue                   4
_journal_name_full               CrystEngComm
_journal_page_first              333
_journal_paper_doi               10.1039/b517513e
_journal_volume                  8
_journal_year                    2006
_chemical_formula_moiety         '2(C12 H24 O2), C4 H4 N2'
_chemical_formula_sum            'C28 H52 N2 O4'
_chemical_formula_weight         480.72
_chemical_name_common            '1:2 pyrazine/dodecanoic acid'
_space_group_IT_number           2
_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
_cell_angle_alpha                89.796(1)
_cell_angle_beta                 88.441(1)
_cell_angle_gamma                75.432(1)
_cell_formula_units_Z            1
_cell_length_a                   5.4447(2)
_cell_length_b                   6.9028(3)
_cell_length_c                   20.307(8)
_cell_measurement_reflns_used    1915
_cell_measurement_temperature    180(2)
_cell_measurement_theta_max      25.55
_cell_measurement_theta_min      3.66
_cell_volume                     738.4(3)
_computing_cell_refinement       'SAINT v.7.06a (Bruker, 2003)'
_computing_data_collection       'APEX2 v.1.0-8 (Bruker-Nonius, 2003)'
_computing_data_reduction        'SAINT v.7.06a (Bruker, 2003)'
_computing_molecular_graphics    'SHELXTL v.6.10 (Sheldrick, 2000)'
_computing_publication_material  'SHELXTL v.6.10 (Sheldrick, 2000)'
_computing_structure_refinement  'SHELXTL v.6.10 (Sheldrick, 2000)'
_computing_structure_solution    'SHELXTL v.6.10 (Sheldrick, 2000)'
_diffrn_ambient_temperature      180(2)
_diffrn_measured_fraction_theta_full 0.875
_diffrn_measured_fraction_theta_max 0.875
_diffrn_measurement_device_type  'Bruker-Nonius X8APEX-II CCD'
_diffrn_measurement_method       'thin-slice \w and \f scans'
_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  0.0258
_diffrn_reflns_av_sigmaI/netI    0.0398
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            3380
_diffrn_reflns_theta_full        25.03
_diffrn_reflns_theta_max         25.03
_diffrn_reflns_theta_min         3.66
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.071
_exptl_absorpt_correction_T_max  0.965
_exptl_absorpt_correction_T_min  0.965
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.081
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       cylinder
_exptl_crystal_F_000             266
_exptl_crystal_size_max          0.60
_exptl_crystal_size_rad          0.25
_refine_diff_density_max         0.273
_refine_diff_density_min         -0.267
_refine_diff_density_rms         0.053
_refine_ls_extinction_coef       0.045(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     160
_refine_ls_number_reflns         2282
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.088
_refine_ls_R_factor_all          0.0639
_refine_ls_R_factor_gt           0.0558
_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^)+(0.0941P)^2^+0.2341P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1640
_refine_ls_wR_factor_ref         0.1724
_reflns_number_gt                1899
_reflns_number_total             2282
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b517513e.txt
_cod_data_source_block           C12
_cod_database_code               7203242