An electric field cell for performing <i>in situ</i> single-crystal synchrotron X-ray diffraction
Saunders, Lucy K.; Yeung, Hamish H.-M.; Warren, Mark R.; Smith, Peter; Gurney, Stuart; Dodsworth, Stephen F.; Vitorica-Yrezabal, Inigo J.; Wilcox, Adrian; Hathaway, Paul V.; Preece, Geoff; Roberts, Paul; Barnett, Sarah A.; Allan, David R.; Journal of Applied Crystallography 54 (2021) 1349–1359; doi:10.1107/S1600576721007469

data_2300681
_publ_section_title
;
 An electric field cell for performing <i>in situ</i> single-crystal
 synchrotron X-ray diffraction
;
_journal_issue                   5
_journal_name_full               'Journal of Applied Crystallography'
_journal_page_first              1349
_journal_page_last               1359
_journal_paper_doi               10.1107/S1600576721007469
_journal_volume                  54
_journal_year                    2021
_chemical_formula_moiety         'C10 H9.19 N2, C4 O4 H0.81'
_chemical_formula_sum            'C14 H10 N2 O4'
_chemical_formula_weight         270.24
_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   difmap
_atom_sites_solution_primary     dual
_audit_creation_date             2020-07-29
_audit_creation_method
;
Olex2 1.3-alpha
(compiled 2020.05.22 svn.r1d9e7f8d for OlexSys, GUI svn.r6115)
;
_cell_angle_alpha                90
_cell_angle_beta                 92.271(5)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   3.8006(2)
_cell_length_b                   11.2165(5)
_cell_length_c                   27.4621(11)
_cell_measurement_reflns_used    6692
_cell_measurement_temperature    298
_cell_measurement_theta_max      20.858864422798966
_cell_measurement_theta_min      1.1136655399800082
_cell_volume                     1169.77(9)
_computing_cell_refinement
'DIALS 2theta refinement, DIALS 3.0.3-g8d758451f-release-hotfix-534f6334'
_computing_data_collection       'GDA - generic data acquisition software'
_computing_data_reduction
;

DIALS 3.0.3-g8d758451f-release-hotfix-534f6334 
(Winter, G. et al., 2018)
dials.scale (Beilsten-Edmands, J. et al., 2020)
XIA2 0.7.44-ge5e34f04-dials-3.0 (Winter, G., 2010)
;
_computing_molecular_graphics    'Olex2 1.3-alpha (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.3-alpha (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL  (Sheldrick, 2008)'
_computing_structure_solution    'SHELXT 2014/4 (Sheldrick, 2014)'
_diffrn_ambient_temperature      298(2)
_diffrn_detector                 'Photon counting pixel array'
_diffrn_detector_type            'Dectris PILATUS 300K'
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.970
_diffrn_measurement_device       '4-circle \k-geometry diffractometer'
_diffrn_measurement_device_type  'Newport IS4CCD'
_diffrn_measurement_method       'shutterless scans'
_diffrn_radiation_monochromator  'Silicon 111'
_diffrn_radiation_wavelength     0.534
_diffrn_reflns_av_R_equivalents  0.0839
_diffrn_reflns_av_unetI/netI     0.0847
_diffrn_reflns_Laue_measured_fraction_full 0.990
_diffrn_reflns_Laue_measured_fraction_max 0.970
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       36
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            15159
_diffrn_reflns_point_group_measured_fraction_full 0.990
_diffrn_reflns_point_group_measured_fraction_max 0.970
_diffrn_reflns_theta_full        18.687
_diffrn_reflns_theta_max         20.894
_diffrn_reflns_theta_min         1.115
_diffrn_source                   Synchrotron
_diffrn_source_details           'Nowell et al. (2012)'
_diffrn_source_type              'Diamond Light Source Beamline I19-2'
_exptl_absorpt_coefficient_mu    0.065
_exptl_absorpt_correction_T_max  1.0
_exptl_absorpt_correction_T_min  0.9996423945163578
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details
;
DIALS 3.0.3-g8d758451f-release-hotfix-534f6334
Scaling & analysis of unmerged intensities, 
absorption correction using spherical harmonics
;
_exptl_crystal_colour            'red-shifted yellow'
_exptl_crystal_density_diffrn    1.534
_exptl_crystal_density_meas      ?
_exptl_crystal_description       block
_exptl_crystal_F_000             560
_exptl_crystal_size_max          1.0
_exptl_crystal_size_mid          2.0
_exptl_crystal_size_min          0.300
_refine_diff_density_max         0.271
_refine_diff_density_min         -0.224
_refine_diff_density_rms         0.056
_refine_ls_extinction_coef       0.023(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   0.828
_refine_ls_hydrogen_treatment    refall
_refine_ls_matrix_type           full
_refine_ls_number_parameters     226
_refine_ls_number_reflns         2813
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      0.828
_refine_ls_R_factor_all          0.0770
_refine_ls_R_factor_gt           0.0495
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0501P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1037
_refine_ls_wR_factor_ref         0.1136
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1578
_reflns_number_total             2813
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            oc5009sup1.cif
_cod_data_source_block           SQABPY_during_high_voltage_2400V
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_exptl_crystal_density_meas' value 'not measured' was
changed to '?' -- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 7556 2019-12-06 15:28:31Z antanas 

 Adding full bibliography for 2300680--2300682.cif.
;
_cod_database_code               2300681
_cod_database_fobs_code          2300681
_shelx_shelxl_version_number     2014/7
_olex2_refinement_description
;
The second squarate H-atom H1 is modelled as disordered 
over two sites (O1 and N1, 80:20 split)
The H-atom has a geometric restraint using a DANG for 
H1 and H1a. The EADP contrains the Uij of the
disorder H1 and H1a atoms to be equal. 

1. Restrained distances
 C12-H1
 2.1 with sigma of 0.04
 C13-H1
 2.1 with sigma of 0.04
2. Uiso/Uaniso restraints and constraints
Uiso(H1A) = Uiso(H1)
3. Others
 Sof(H1)=1-FVAR(1)
 Sof(H1A)=FVAR(1)
;
_shelx_res_checksum              56517
_shelx_hkl_checksum              57242
_olex2_submission_special_instructions 'No special instructions were received'