LiF — powder X-ray CW — doublet¶

Verifies Cu Kα₁/Kα₂ doublet handling on the LiF pseudo-Voigt reference.

Note: the Kα₁/Kα₂ doublet is produced by an EasyDiffraction-level implementation on top of the calculation engine — the engine is run twice (at λ₁ and λ₂) and the two patterns are summed by the intensity ratio — because neither cryspy nor the CFL-based crysfml API computes the doublet natively.

Refinement: none — every parameter is taken from the FullProf reference; only the calculated patterns are compared.

In [2]:

import easydiffraction as edi
from easydiffraction import ExperimentFactory
from easydiffraction import StructureFactory
from easydiffraction.analysis import verification as verify

import easydiffraction as edi from easydiffraction import ExperimentFactory from easydiffraction import StructureFactory from easydiffraction.analysis import verification as verify

Build the project¶

In [3]:

project = edi.Project()

project = edi.Project()

Define the structure¶

In [4]:

structure = StructureFactory.from_scratch(name='lif')

structure.space_group.name_h_m = 'F m -3 m'  # FullProf Space group symbol
structure.cell.length_a = 4.026700  # FullProf a

structure.atom_sites.create(
    id='Li1',  # FullProf Atom
    type_symbol='Li',  # FullProf Typ
    fract_x=0.0,  # FullProf X
    fract_y=0.0,  # FullProf Y
    fract_z=0.0,  # FullProf Z
    adp_type='Biso',  # FullProf Biso
    adp_iso=1.20000,  # FullProf Biso
)
structure.atom_sites.create(
    id='F1',  # FullProf Atom
    type_symbol='F',  # FullProf Typ
    fract_x=0.5,  # FullProf X
    fract_y=0.5,  # FullProf Y
    fract_z=0.5,  # FullProf Z
    adp_type='Biso',  # FullProf Biso
    adp_iso=0.80000,  # FullProf Biso
)

project.structures.add(structure)

structure = StructureFactory.from_scratch(name='lif') structure.space_group.name_h_m = 'F m -3 m' # FullProf Space group symbol structure.cell.length_a = 4.026700 # FullProf a structure.atom_sites.create( id='Li1', # FullProf Atom type_symbol='Li', # FullProf Typ fract_x=0.0, # FullProf X fract_y=0.0, # FullProf Y fract_z=0.0, # FullProf Z adp_type='Biso', # FullProf Biso adp_iso=1.20000, # FullProf Biso ) structure.atom_sites.create( id='F1', # FullProf Atom type_symbol='F', # FullProf Typ fract_x=0.5, # FullProf X fract_y=0.5, # FullProf Y fract_z=0.5, # FullProf Z adp_type='Biso', # FullProf Biso adp_iso=0.80000, # FullProf Biso ) project.structures.add(structure)

Load the FullProf reference¶

In [5]:

FULLPROF_PROJECT_DIR = 'pd-xray-cwl_lif'
FULLPROF_PRF_FILE = 'lif_doublet_unpolarized.prf'
FULLPROF_SUM_FILE = 'lif_doublet_unpolarized.sum'
FULLPROF_BAC_FILE = 'lif_doublet_unpolarized.bac'
FULLPROF_LABEL = verify.fullprof_label(FULLPROF_PROJECT_DIR, FULLPROF_SUM_FILE)

FULLPROF_ZERO = 0.0  # FullProf Zero
FULLPROF_SCALE = 0.01  # FullProf Scale
FULLPROF_WAVELENGTH_1 = 1.540560  # FullProf Lambda1
FULLPROF_WAVELENGTH_2 = 1.544400  # FullProf Lambda2
FULLPROF_WAVELENGTH_2_TO_1_RATIO = 0.50000  # FullProf Ratio
FULLPROF_U = 0.048457  # FullProf U
FULLPROF_V = -0.083053  # FullProf V
FULLPROF_W = 0.040000  # FullProf W
FULLPROF_X = 0.0  # FullProf X
FULLPROF_Y = 0.049268  # FullProf Y
FULLPROF_WDT = 48.0  # FullProf Wdt

x, calc_fullprof = verify.load_fullprof_calc_profile(
    FULLPROF_PROJECT_DIR,
    FULLPROF_PRF_FILE,
    FULLPROF_BAC_FILE,
    FULLPROF_ZERO,
)

FULLPROF_PROJECT_DIR = 'pd-xray-cwl_lif' FULLPROF_PRF_FILE = 'lif_doublet_unpolarized.prf' FULLPROF_SUM_FILE = 'lif_doublet_unpolarized.sum' FULLPROF_BAC_FILE = 'lif_doublet_unpolarized.bac' FULLPROF_LABEL = verify.fullprof_label(FULLPROF_PROJECT_DIR, FULLPROF_SUM_FILE) FULLPROF_ZERO = 0.0 # FullProf Zero FULLPROF_SCALE = 0.01 # FullProf Scale FULLPROF_WAVELENGTH_1 = 1.540560 # FullProf Lambda1 FULLPROF_WAVELENGTH_2 = 1.544400 # FullProf Lambda2 FULLPROF_WAVELENGTH_2_TO_1_RATIO = 0.50000 # FullProf Ratio FULLPROF_U = 0.048457 # FullProf U FULLPROF_V = -0.083053 # FullProf V FULLPROF_W = 0.040000 # FullProf W FULLPROF_X = 0.0 # FullProf X FULLPROF_Y = 0.049268 # FullProf Y FULLPROF_WDT = 48.0 # FullProf Wdt x, calc_fullprof = verify.load_fullprof_calc_profile( FULLPROF_PROJECT_DIR, FULLPROF_PRF_FILE, FULLPROF_BAC_FILE, FULLPROF_ZERO, )

Create the experiment¶

In [6]:

experiment = ExperimentFactory.from_scratch(
    name='lif',
    sample_form='powder',
    beam_mode='constant wavelength',
    radiation_probe='xray',
    scattering_type='bragg',
)
verify.set_reference_as_measured(experiment, x, calc_fullprof)

experiment.linked_structures.create(structure_id='lif', scale=FULLPROF_SCALE)

experiment.instrument.setup_wavelength = FULLPROF_WAVELENGTH_1
experiment.instrument.setup_wavelength_2 = FULLPROF_WAVELENGTH_2
experiment.instrument.setup_wavelength_2_to_1_ratio = FULLPROF_WAVELENGTH_2_TO_1_RATIO
experiment.instrument.calib_twotheta_offset = FULLPROF_ZERO

experiment.peak.type = 'pseudo-voigt'
experiment.peak.broad_gauss_u = FULLPROF_U
experiment.peak.broad_gauss_v = FULLPROF_V
experiment.peak.broad_gauss_w = FULLPROF_W
experiment.peak.broad_lorentz_x = FULLPROF_X
experiment.peak.broad_lorentz_y = FULLPROF_Y

experiment.peak.cutoff_fwhm = FULLPROF_WDT

project.experiments.add(experiment)

experiment = ExperimentFactory.from_scratch( name='lif', sample_form='powder', beam_mode='constant wavelength', radiation_probe='xray', scattering_type='bragg', ) verify.set_reference_as_measured(experiment, x, calc_fullprof) experiment.linked_structures.create(structure_id='lif', scale=FULLPROF_SCALE) experiment.instrument.setup_wavelength = FULLPROF_WAVELENGTH_1 experiment.instrument.setup_wavelength_2 = FULLPROF_WAVELENGTH_2 experiment.instrument.setup_wavelength_2_to_1_ratio = FULLPROF_WAVELENGTH_2_TO_1_RATIO experiment.instrument.calib_twotheta_offset = FULLPROF_ZERO experiment.peak.type = 'pseudo-voigt' experiment.peak.broad_gauss_u = FULLPROF_U experiment.peak.broad_gauss_v = FULLPROF_V experiment.peak.broad_gauss_w = FULLPROF_W experiment.peak.broad_lorentz_x = FULLPROF_X experiment.peak.broad_lorentz_y = FULLPROF_Y experiment.peak.cutoff_fwhm = FULLPROF_WDT project.experiments.add(experiment)

Peak profile type for experiment 'lif' changed to

pseudo-voigt

edi-cryspy VS FullProf¶

In [7]:

experiment.calculator.type = 'cryspy'

project.analysis.calculate()
calc_ed_cryspy = experiment.data.intensity_calc
LABEL_ED_CRYSPY = verify.engine_label('cryspy')

project.display.pattern_comparison(
    'lif',
    reference=calc_fullprof,
    candidate=calc_ed_cryspy,
    reference_label=FULLPROF_LABEL,
    candidate_label=LABEL_ED_CRYSPY,
)

experiment.calculator.type = 'cryspy' project.analysis.calculate() calc_ed_cryspy = experiment.data.intensity_calc LABEL_ED_CRYSPY = verify.engine_label('cryspy') project.display.pattern_comparison( 'lif', reference=calc_fullprof, candidate=calc_ed_cryspy, reference_label=FULLPROF_LABEL, candidate_label=LABEL_ED_CRYSPY, )

Calculator for experiment 'lif' already set to

cryspy

Loading plot…

Agreement check¶

In [8]:

# cryspy matches FullProf, so it is gated as a regression test.
verify.assert_patterns_agree(
    [
        (f'{LABEL_ED_CRYSPY} vs {FULLPROF_LABEL}', calc_fullprof, calc_ed_cryspy),
    ],
)

# cryspy matches FullProf, so it is gated as a regression test. verify.assert_patterns_agree( [ (f'{LABEL_ED_CRYSPY} vs {FULLPROF_LABEL}', calc_fullprof, calc_ed_cryspy), ], )

	Comparison	Metric	Expected	Actual	OK
1	edi 0.19.0 (cryspy 0.12.1) vs FullProf 7.95	Profile diff (%)	< 2.5	0.21	✅
2		Max deviation (%)	< 6	0.19	✅
3		Area ratio	0.99 to 1.01	1.0003	✅
4		Shape correlation	> 0.999	1.0000	✅

Out[8]:

True

In [ ]: