Four-circle single-crystal neutron diffractometer at the High Flux Isotope Reactor
Chakoumakos, Bryan C.; Cao, Huibo; Ye, Feng; Stoica, Alexandru D.; Popovici, Mihai; Sundaram, Madhan; Zhou, Wenduo; Hicks, J. Steve; Lynn, Gary W.; Riedel, Richard A.; Journal of Applied Crystallography 44 (2011) 655–658; doi:10.1107/S0021889811012301

data_2300356
_publ_section_title
;
 Four-circle single-crystal neutron diffractometer at the High Flux
 Isotope Reactor
;
_journal_coeditor_code           KO5139
_journal_issue                   3
_journal_name_full               'Journal of Applied Crystallography'
_journal_page_first              655
_journal_page_last               658
_journal_paper_doi               10.1107/S0021889811012301
_journal_volume                  44
_journal_year                    2011
_chemical_formula_moiety         'H2C2O4 2H2O'
_chemical_formula_sum            'C2 H6 O6'
_chemical_formula_weight         126.063
_chemical_name_common            'alpha oxalic acid dihydrate'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 106.26(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   6.0514(2)
_cell_length_b                   3.5482(16)
_cell_length_c                   11.996(4)
_cell_measurement_temperature    293(2)
_cell_volume                     247.27(14)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.965
_diffrn_measured_fraction_theta_max 0.965
_diffrn_measurement_device_type  'Huber four-circle diffractometer'
_diffrn_measurement_method       'omega scans, bisecting mode'
_diffrn_radiation_monochromator  silicon
_diffrn_radiation_probe          neutron
_diffrn_radiation_source         'High Flux Isotope Reactor, ORNL'
_diffrn_radiation_type           neutron
_diffrn_radiation_wavelength     1.00000
_diffrn_reflns_av_R_equivalents  0.0338
_diffrn_reflns_av_sigmaI/netI    0.1258
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       4
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            667
_diffrn_reflns_theta_full        42.94
_diffrn_reflns_theta_max         42.94
_diffrn_reflns_theta_min         4.89
_exptl_absorpt_coefficient_mu    0.168
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.711
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             51
_exptl_crystal_size_max          2
_exptl_crystal_size_mid          2
_exptl_crystal_size_min          1.5
_refine_diff_density_max         0.475
_refine_diff_density_min         -0.787
_refine_ls_extinction_coef       1.54(15)
_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   0.956
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     65
_refine_ls_number_reflns         613
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.956
_refine_ls_R_factor_all          0.1877
_refine_ls_R_factor_gt           0.0563
_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^)+(0.1137P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1505
_refine_ls_wR_factor_ref         0.1721
_reflns_number_gt                332
_reflns_number_total             613
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ko5139.cif
_cod_data_source_block           shelxl
_cod_original_cell_volume        247.27(16)
_cod_original_sg_symbol_H-M      P21/n
_cod_database_code               2300356