Project
The Project serves as a container for all data and metadata associated with a diffraction experiment. It acts as the top-level entity in EasyDiffraction, ensuring structured organization and easy access to relevant information. Each project can contain multiple experimental datasets, with each dataset containing contribution from multiple physical models.
Project structure
The example below illustrates a typical project structure for a constant-wavelength powder neutron diffraction experiment:
Each file within the Project directory plays a crucial role in defining, analyzing, and refining diffraction experiments.
📁 La0.5Ba0.5CoO3 - Project directory. ├── 📄 project.cif - Main project description file. ├── 📁 models - Folder with individual crystallographic phases. │ ├── 📄 lbco.cif - File with La0.5Ba0.5CoO3 phase parameters. │ └── ... ├── 📁 experiments - Folder with instrumental parameters and measured data. │ ├── 📄 hrpt.cif - Measured data from HRPT@PSI & instrumental parameters. │ └── ... └── 📁 summary └── 📄 report.cif - Summary report after structure refinement.
Project Files
Below is a detailed breakdown of the content within each project file.
project.cif
This file provides an overview of the project, linking relevant models and experimental datasets.
data_La0.5Ba0.5CoO3 _project.description "neutrons, powder, constant wavelength, HRPT@PSI" loop_ _model.cif_file_name lbco.cif loop_ _experiment.cif_file_name hrpt.cif
models / lbco.cif
This file contains crystallographic information, including space group, unit cell parameters, and atomic positions.
data_lbco _space_group.name_H-M_alt "P m -3 m" _space_group.IT_coordinate_system_code 1 _cell.length_a 3.8909(1) _cell.length_b 3.8909 _cell.length_c 3.8909 _cell.angle_alpha 90 _cell.angle_beta 90 _cell.angle_gamma 90 loop_ _atom_site.label _atom_site.type_symbol _atom_site.fract_x _atom_site.fract_y _atom_site.fract_z _atom_site.occupancy _atom_site.adp_type _atom_site.B_iso_or_equiv La La 0 0 0 0.5 Biso 0.4958 Ba Ba 0 0 0 0.5 Biso 0.4943 Co Co 0.5 0.5 0.5 1 Biso 0.2567 O O 0 0.5 0.5 1 Biso 1.4041
experiments / hrpt.cif
This file contains instrumental parameters and measured diffraction data.
data_hrpt _diffrn_radiation.probe neutron _diffrn_radiation_wavelength.wavelength 1.494 _pd_calib.2theta_offset 0.6225(4) _pd_instr.resolution_u 0.0834 _pd_instr.resolution_v -0.1168 _pd_instr.resolution_w 0.123 _pd_instr.resolution_x 0 _pd_instr.resolution_y 0.0797 _pd_instr.reflex_asymmetry_p1 0 _pd_instr.reflex_asymmetry_p2 0 _pd_instr.reflex_asymmetry_p3 0 _pd_instr.reflex_asymmetry_p4 0 loop_ _pd_phase_block.id _pd_phase_block.scale lbco 9.0976(3) loop_ _pd_background.line_segment_X _pd_background.line_segment_intensity _pd_background.X_coordinate 10 174.3 2theta 20 159.8 2theta 30 167.9 2theta 50 166.1 2theta 70 172.3 2theta 90 171.1 2theta 110 172.4 2theta 130 182.5 2theta 150 173.0 2theta 165 171.1 2theta loop_ _pd_meas.2theta_scan _pd_meas.intensity_total _pd_meas.intensity_total_su 10.00 167 12.6 10.05 157 12.5 10.10 187 13.3 10.15 197 14.0 10.20 164 12.5 10.25 171 13.0 ... 164.60 153 20.7 164.65 173 30.1 164.70 187 27.9 164.75 175 38.2 164.80 168 30.9 164.85 109 41.2
Now that the Project has been defined, you can proceed to the next step: Model.