Fitting PD-NEUT-TOF
Si-SEPD¶
This example shows how to refine the crystal structure parameters of Si from neutron diffraction data in a time-of-flight experiment performed on SEPD diffractometer at Argonne.
Import¶
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import easydiffraction as ed
import easydiffraction as ed
Job¶
Create a job — the main object to store all the information
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job = ed.Job(type='tof')
job = ed.Job(type='tof')
Model¶
Create a phase object
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phase = ed.Phase(name='si')
phase = ed.Phase(name='si')
Set space group
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phase.space_group.name_hm_alt = 'F d -3 m'
phase.space_group.name_hm_alt = 'F d -3 m'
Set cell parameters
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phase.cell.length_a = 5.43146
phase.cell.length_a = 5.43146
Add atoms
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phase.atom_sites.append(label='Si',
type_symbol='Si',
fract_x=0,
fract_y=0,
fract_z=0,
occupancy=1,
b_iso_or_equiv=0.529)
phase.atom_sites.append(label='Si',
type_symbol='Si',
fract_x=0,
fract_y=0,
fract_z=0,
occupancy=1,
b_iso_or_equiv=0.529)
Add phase to the job object
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job.add_phase(phase=phase)
print(job.phases)
job.add_phase(phase=phase)
print(job.phases)
Several values of it_coordinate_system_code have been defined: 2, 1 The default value has been choosen:'2'. Several values of it_coordinate_system_code have been defined: 2, 1 The default value has been choosen:'2'. Collection of 1 phases: ['si']
Show phase info in CIF format
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phase = job.phases['si']
print(phase.cif)
phase = job.phases['si']
print(phase.cif)
data_si _cell_length_a 5.43146 _cell_length_b 5.43146 _cell_length_c 5.43146 _cell_angle_alpha 90.00000000 _cell_angle_beta 90.00000000 _cell_angle_gamma 90.00000000 _space_group_name_H-M_ref 'F d -3 m' _space_group_IT_coordinate_system_code 1 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 Si Si 0.00000000 0.00000000 0.00000000 1.00000000 Biso 0.529
Display the crystal structure of a given model
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job.show_crystal_structure(id='si')
job.show_crystal_structure(id='si')
You appear to be running in JupyterLab (or JavaScript failed to load for some other reason). You need to install the 3dmol extension:
jupyter labextension install jupyterlab_3dmol
Experiment¶
Load experimentally measured data from a file in XYE format
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job.add_experiment_from_file('data/sepd.xye')
job.add_experiment_from_file('data/sepd.xye')
Display the experimentally measured data
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job.show_experiment_chart()
job.show_experiment_chart()