On the importance of low-frequency modes in predicting pressure-induced phase transitions.
Hoser, Anna; Zwolenik, Aleksandra; Makal, Anna; Physical chemistry chemical physics : PCCP 26 (2024) 20745–20749; doi:10.1039/d4cp02368d

data_7249114
_publ_section_title
;
 On the importance of low-frequency modes in predicting pressure-induced
 phase transitions.
;
_journal_issue                   31
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              20745
_journal_page_last               20749
_journal_paper_doi               10.1039/d4cp02368d
_journal_volume                  26
_journal_year                    2024
_chemical_formula_moiety         '2(C10 H7 O)'
_chemical_formula_sum            'C20 H14 O2'
_chemical_formula_weight         286.31
_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'
_atom_sites_solution_hydrogens   geom
_audit_creation_date             2024-01-25
_audit_creation_method
;
Olex2 1.5-alpha
(compiled 2023.11.24 svn.r209d9fb for OlexSys, GUI svn.r6869)
;
_audit_update_record
;
2024-02-13 deposited with the CCDC.	2024-07-24 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 96.68(5)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.901(2)
_cell_length_b                   22.685(5)
_cell_length_c                   6.897(11)
_cell_measurement_reflns_used    825
_cell_measurement_temperature    292.3(5)
_cell_measurement_theta_max      29.9840
_cell_measurement_theta_min      2.7450
_cell_volume                     1228(2)
_computing_cell_refinement       'CrysAlisPro 1.171.42.36a (Rigaku OD, 2021)'
_computing_data_collection       'CrysAlisPro 1.171.42.36a (Rigaku OD, 2021)'
_computing_data_reduction        'CrysAlisPro 1.171.42.36a (Rigaku OD, 2021)'
_computing_molecular_graphics    'Olex2 1.5-alpha (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5-alpha (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2013/2 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_pressure         2000000
_diffrn_ambient_temperature      292.15
_diffrn_crystal_treatment
'pressurized slowly/rapidly in paratone oil as a hydrostatic medium'
_diffrn_detector_area_resol_mean 5.2195
_diffrn_detector_type            Atlas
_diffrn_measured_fraction_theta_full 0.492
_diffrn_measured_fraction_theta_max 0.479
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -44.00  26.00   0.50   25.00    --    2.10  13.00  -3.00  140
  2  \w    -22.00   4.00   0.50   75.00    --   18.10 -19.00-150.00   52
  3  \w     -7.00  18.00   0.50   75.00    --   18.10  53.00 162.00   50
  4  \w     -7.00  18.00   0.50   75.00    --   18.10  53.00 -17.00   50
  5  \w      6.00  31.00   0.50   75.00    --   18.10  13.00  -3.00   50
  6  \w    -18.00   8.00   0.50   75.00    --  -19.97 -26.00   7.00   52
  7  \w    -10.00  11.00   0.50   75.00    --  -19.97 -70.00-157.00   42
  8  \w    -18.00   7.00   0.50   75.00    --  -19.97 -53.00  17.00   50
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at home/near, Atlas'
_diffrn_measurement_method       '\w scans'
_diffrn_measurement_specimen_support
'Diamond Anvil Cell, effective opening angle of 50 deg.'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1322
_diffrn_reflns_av_unetI/netI     0.1659
_diffrn_reflns_Laue_measured_fraction_full 0.492
_diffrn_reflns_Laue_measured_fraction_max 0.479
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       26
_diffrn_reflns_limit_k_min       -28
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -3
_diffrn_reflns_number            4771
_diffrn_reflns_point_group_measured_fraction_full 0.492
_diffrn_reflns_point_group_measured_fraction_max 0.479
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.371
_diffrn_reflns_theta_min         2.595
_exptl_absorpt_coefficient_mu    0.099
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.27933
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.36a (Rigaku Oxford Diffraction, 2021)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear yellow'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.549
_exptl_crystal_description       plate
_exptl_crystal_F_000             600
_exptl_crystal_preparation
'Mounted in a Diamond-Anvil Cell using paratone oil as pressure medium.'
_exptl_crystal_pressure_history  'Pressurized to 1.98 GPa.'
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.278
_refine_diff_density_min         -0.209
_refine_diff_density_rms         0.059
_refine_ls_extinction_coef       0.011(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   1.034
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     202
_refine_ls_number_reflns         1204
_refine_ls_number_restraints     108
_refine_ls_restrained_S_all      0.995
_refine_ls_R_factor_all          0.2403
_refine_ls_R_factor_gt           0.1015
_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^)+(0.1658P)^2^+0.3370P]
 where P=(Fo^2^+2Fc^2^)/3
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2506
_refine_ls_wR_factor_ref         0.3586
_reflns_Friedel_coverage         0.000
_reflns_number_gt                436
_reflns_number_total             1204
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4cp02368d2.cif
_cod_data_source_block           2papb_2p0gpa
_cod_depositor_comments
'Adding full bibliography for 7249110--7249118.cif.'
_cod_database_code               7249114
_shelxl_version_number           2013-2
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Rigid body (RIGU) restrains
 C1B, C2B, C3B, C4B, C5B, C6B, C7B, C8B
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
 C1A, C2A, C3A, C4A, C5A, C6A, C7A, C8A
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
3.a Aromatic/amide H refined with riding coordinates:
 C1A(H1A), C5A(H5A), C6A(H6A), C7A(H7A), C1B(H1B), C5B(H5B), C6B(H6B), C7B(H7B)
3.b Idealised Me refined as rotating group:
 C10A(H10A,H10B,H10C), C10B(H10D,H10E,H10F)
;
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;