items to include in a powder diffraction CIF

Full definitions of the data items starting with _pd are given in the powder CIF dictionary and full definitions of the other data items are given in the core CIF dictionary. Data items that are not relevant to a particular study do not need to be included in the CIF.

Text items (for Acta Cryst. E, include the text of your paper in the CIF using the data names below; for Acta Cryst. C, either include the text in the CIF or submit it as a separate WORD document)
_publ_contact_author_name Contact author's name
_publ_contact_author_address Contact author's address
_publ_contact_author_email E-mail address to be published
_publ_contact_author_fax For editorial communications
_publ_contact_author_phone For editorial communications
_publ_contact_letter Letter of submission, with date
_publ_requested_journal E.g. 'Acta Crystallographica Section C'
_publ_requested_category Acta Cryst. C: FA. Acta Cryst. E: HI/HM/HO, GI/GM/GO or AD
_publ_section_title Title of paper
_publ_section_title_footnote Footnote to title of paper
_publ_author_name List of author(s) name(s)
_publ_author_footnote Footnote(s) to author(s) name(s)
_publ_author_address Author(s) address(es)
_publ_section_synopsis A synopsis should be supplied for all articles
_publ_section_abstract Abstract of paper in English
_publ_section_comment Discussion of study
_publ_section_acknowledgements Acknowledgements
_publ_section_references References
_publ_section_figure_captions Legends to figures
 
Experimental data
_chemical_formula_sum Chemical formula as sum of elements
_chemical_formula_moiety Chemical formula in moieties
_chemical_formula_weight Chemical formula mass (Da)
_chemical_melting_point Melting point (K)
_space_group_crystal_system Code for crystal system
_space_group_name_H-M_alt Hermann-Mauguin space-group symbol
_space_group_name_Hall Hall space-group symbol
_symmetry_equiv_pos_as_xyz Equivalent positions in order used by _geom_
_cell_length_a
_cell_length_b
_cell_length_c
Unit-cell lengths (Å)
_cell_angle_alpha
_cell_angle_beta
_cell_angle_gamma
Unit-cell angles (°)
_cell_volume Unit-cell volume (Å3)
_cell_formula_units_Z Number of formulae per unit cell
_exptl_crystal_density_diffrn Density calculated from unit cell and contents (Mg m-3)
_publ_section_exptl_prep Compound preparation details
_pd_prep_cool_rate Cooling rate for preparation of specimen (K min-1)
_pd_prep_pressure Pressure at which specimen was prepared (kPa)
_pd_prep_temperature Temperature at which specimen was prepared (K)
_pd_spec_size_axial Specimen dimension perpendicular to the equatorial plane (mm). (The equatorial plane contains the incident and diffracted beams.)
_pd_spec_size_equat Specimen dimension parallel to the scattering vector in transmission (mm)
_pd_spec_size_thick Specimen dimension parallel to the scattering vector in reflection (mm)
_pd_spec_mounting Details of the container or support (used when scattering from the container or support contributes to the diffraction profile)
_pd_spec_mount_mode Options: 'reflection' or 'transmission'
_pd_spec_shape Options: 'cylinder', 'flat_sheet' or 'irregular'
_pd_char_particle_morphology The morphology and size of the particles in the specimen
_pd_char_colour Use ICDD colour codes: colourless, white, black, gray, brown, red, pink, orange, yellow, green, blue, violet. Colours may be modified using the prefixes: light, dark, whitish, blackish, grayish, brownish, reddish, pinkish, orangish, yellowish, greenish, bluish. Intermediate hues may be indicated by using two colours, e.g. blue-green or bluish-green. For metallic materials the term `metallic' may be added, e.g. copper metal may be described as reddish-orange-metallic
_diffrn_radiation_type Radiation type (e.g. neutron or Mo Kα)
_diffrn_radiation_wavelength Radiation wavelength (Å) (angle-dispersive measurements only)
_diffrn_radiation_monochromator Method used to obtain monochromatic radiation (if relevant) (e.g.  'Ge 220')
_diffrn_ambient_temperature Measurement temperature (K)
_diffrn_measurement_device_type Diffractometer make and type
_diffrn_detector_area_resol_mean Resolution of area detector (pixels mm-1) (if relevant)
_pd_meas_scan_method Options: 'step', 'cont', 'tof', 'fixed' or 'disp' (= dispersive)
_exptl_absorpt_coefficient_mu Linear absorption coefficient (mm-1) (for transmission experiments)
_exptl_absorpt_correction_type Code for absorption correction (if applicable)
_exptl_absorpt_process_details Literature reference for absorption correction [e.g. '(North et al., 1968)'] (if applicable)
_exptl_absorpt_correction_T_min Minimum transmission factor from corrections (if applicable)
_exptl_absorpt_correction_T_max Maximum transmission factor from corrections (if applicable)
_pd_meas_number_of_points
Number of points in the measured (not processed) powder pattern
_pd_meas_2theta_range_min Minimum value of 2θ for the measured powder pattern (°) (angle-dispersive measurements only)
_pd_meas_2theta_range_max Maximum value of 2θ for the measured powder pattern (°) (angle-dispersive measurements only)
_pd_meas_2theta_range_inc Increment between points (°) in the measured powder pattern (angle-dispersive measurements only)
_pd_instr_dist_src/spec Distance from radiation source to specimen (mm)
_pd_instr_dist_spec/detc Distance from specimen to detector (mm)
_pd_meas_2theta_fixed
2θ diffractometer angle (°) in a white-beam fixed-angle experiment (time-of-flight only)
_pd_proc_2theta_range_min Minimum value of 2θ for the powder pattern used in the refinement (i.e. after processing and application of corrections) (°) (angle-dispersive measurements only)
_pd_proc_2theta_range_max Maximum value of 2θ for the powder pattern used in the refinement (°) (angle-dispersive measurements only)
_pd_proc_2theta_range_inc Increment between points (°) in the powder pattern used in the refinement (angle-dispersive measurements only)
_pd_proc_wavelength Wavelength (after calibration)
_pd_block_diffractogram_id The ID of the data block containing the powder diffraction profile
_pd_proc_ls_profile_function Profile function
_pd_proc_ls_background_function Treatment of background
_pd_proc_ls_pref_orient_corr Preferred orientation correction (if applied)
_refine_ls_number_parameters Number of parameters refined
_refine_ls_number_restraints Number of restrained parameters
_refine_ls_number_constraints Number of constrained parameters
_refine_ls_weighting_scheme Options: 'sigma' (weights based on measured s.u.'s) or 'calc' (calculated)
_refine_ls_weighting_details Weighting expression
_refine_ls_hydrogen_treatment Code for H-atom treatment
_refine_ls_shift/su_max Maximum shift/s.u. ratio after final refinement cycle
_refine_diff_density_max
_refine_diff_density_min
Maximum/minimum values of final difference map (e Å-3)
_refine_ls_extinction_method Description of extinction correction (if applicable)
_refine_ls_extinction_coef Extinction coefficient (if applicable)
_pd_proc_ls_prof_R_factor Rp
_pd_proc_ls_prof_wR_factor Rwp
_pd_proc_ls_prof_wR_expected Rexp
_refine_ls_R_I_factor RI
_refine_ls_R_Fsqd_factor R(F2)
_refine_ls_R_factor_all Conventional crystallographic R factor, R(F)
_refine_ls_goodness_of_fit_all This is the same as chi, i.e. the square root of 'chi squared'
_refine_ls_restrained_S_all Goodness of fit including restraints
_publ_section_exptl_refinement Specialdetails of the refinement
_computing_data_collection Reference to data-collection software
_computing_cell_refinement Reference to cell-refinement software
_computing_data_reduction Reference to data-reduction software
_computing_structure_solution Reference to structure-solution software
_computing_structure_refinement Reference to structure-refinement software
_computing_molecular_graphics Reference to visualization software
_computing_publication_material Reference to publication preparation software
 
loop_
_atom_type_symbol Atom type symbol (usually element symbol)
_atom_type_description Description of atom type
_atom_type_scat_source Reference to scattering factors applied
_atom_type_scat_dispersion_real Real anomalous-dispersion value applied
_atom_type_scat_dispersion_imag Imaginary anomalous-dispersion value applied
_atom_type_scat_length_neutron Bound coherent scattering length (fm) (if applicable)
 
loop_
_atom_site_label Unique label identifying the atom site
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
Fractional coordinates of atom site
_atom_site_U_iso_or_equiv Isotropic atomic displacement parameter, or equivalent from anisotropic atomic displacement parameters
_atom_site_occupancy Occupancy fraction for site (default is 1.0)
_atom_site_disorder_assembly Code that identifies functional group suffering disorder
_atom_site_disorder_group Code that identifies disorder group
_atom_site_adp_type Atomic displacement parameter type
 
loop_
_atom_site_aniso_label Unique label identifying the atom site (if atom refined anisotropically)
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Elements of anisotropic atomic displacement parameter tensor (if atom refined anisotropically)
 
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
Labels identifying the atom sites 1 and 2
_geom_bond_site_symmetry_1
_geom_bond_site_symmetry_2
Symmetry codes (e.g. 2_554) for atom sites 1 and 2
_geom_bond_distance Distancebetween atom sites 1 and 2 (Å)
_geom_bond_publ_flag Flag for print request (yes or no)
 
loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
Labels identifying the atom sites 1, 2 and 3
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_2
_geom_angle_site_symmetry_3
Symmetry codes for atom sites 1, 2 and 3
Angle between atom sites 1, 2 and 3 (°)
_geom_angle_publ_flag Flag for print request (yes or no)
 
loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
Labels identifying the atom sites 1, 2, 3 and 4
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
Symmetry codes for atom sites 1, 2, 3 and 4
_geom_torsion Torsion angle between atom sites 1, 2, 3 and 4 (°)
_geom_torsion_publ_flag Flag for print request (yes or no)
 
loop_
_geom_hbond_atom_site_label_D Donor-atom label in hydrogen bond
_geom_hbond_atom_site_label_H H-atom label in hydrogen bond
_geom_hbond_atom_site_label_A Acceptor-atom label in hydrogen bond
_geom_hbond_site_symmetry_D Symmetry code for donor site
_geom_hbond_site_symmetry_H Symmetry code for H-atom site
_geom_hbond_site_symmetry_A Symmetry code for acceptor site
_geom_hbond_distance_DH Donor atom-to-H-atom distance (Å)
_geom_hbond_distance_HA H-atom-to-acceptor atom distance (Å)
_geom_hbond_distance_DA Donor atom-to-acceptor atom distance (Å)
_geom_hbond_angle_DHA Donor to H to acceptor angle (°)
_geom_hbond_publ_flag Flag for print request (yes or no)
 
Additional items to be published
The data items listed above will be included in a paper for Acta Crystallographica Section C or E.  To request that the data associated with any data item not in the list above are also included, the data item should be specified using _publ_manuscript_incl_extra_item and _publ_manuscript_incl_extra_defn, and should also be listed in _publ_contact_letter
 
loop_
_publ_manuscript_incl_extra_item Additional data item to be published
_publ_manuscript_incl_extra_defn Is item defined in the core CIF dictionary? (yes or no)
 
Powder profile
Each powder profile should be provided as a separate file. The data should include at least one item from each of the lists below. Two-theta values may be specified by using *_2theta_range_min, _max and _inc outside the data loop.
_pd_block_id Should match the _pd_block_diffractogram_id used above to link the refinement with the diffraction profile
_pd_meas_2theta_range_min, *_max, *_inc
_pd_meas_2theta_scan
_pd_proc_2theta_range_min, *_max, *_inc
_pd_meas_2theta_corrected
_pd_meas_time_of_flight
_pd_meas_position
_pd_proc_energy_incident
_pd_proc_wavelength
_pd_proc_d_spacing
_pd_proc_recip_len_Q
The data corresponding to the ordinate of the Rietveld plot. If _pd_meas_time_of_flight, _pd_meas_position or _pd_proc_energy_incident are used, _pd_proc_d_spacing or _pd_proc_recip_len_Q should also be included.
_pd_meas_counts_total
_pd_meas_intensity_total
_pd_proc_intensity_total
_pd_proc_intensity_net
The observed (or processed) intensity values. If _pd_meas_counts_total is not used, standard uncertainties should be specified or least-squares weights should be included.
_pd_meas_counts_background
_pd_meas_counts_container
_pd_meas_intensity_background
_pd_meas_intensity_container
_pd_proc_intensity_bkg_calc
_pd_proc_intensity_bkg_fix
Details of the background
_pd_proc_ls_weight Rietveld refinements are almost always weighted by the reciprocal of the intensity values or the reciprocal of the intensity standard uncertainties squared. If any other weighting has been used, this should be specified. If data are excluded from the fit, _pd_proc_ls_weight should be specified for all points with a zero value for the excluded points
_pd_calc_intensity_net
_pd_calc_intensity_total
The calculated pattern


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