Getting Started

Installation

XRayLabTool requires Julia 1.10 or later.

using Pkg
Pkg.add(url="https://github.com/imewei/XRayLabTool.git")

Single material calculation

Use calculate_single_material_properties for one material:

using XRayLabTool

# SiO2 at energies from 5 to 20 keV, density 2.2 g/cm³
result = calculate_single_material_properties("SiO2", collect(5.0:1.0:20.0), 2.2)

# Access scalar properties
result.formula              # "SiO2"
result.molecular_weight     # 60.08 g/mol
result.number_of_electrons  # 30.0
result.electron_density     # electrons/ų

# Access energy-dependent vector properties
result.energy               # [5.0, 6.0, ..., 20.0] keV
result.wavelength           # corresponding wavelengths in Å
result.dispersion           # δ values
result.absorption           # β values
result.f1                   # real scattering factor (per molecule)
result.f2                   # imaginary scattering factor (per molecule)
result.critical_angle       # critical angles in degrees
result.attenuation_length   # 1/e attenuation lengths in cm
result.real_sld             # real part of SLD in Å⁻²
result.imag_sld             # imaginary part of SLD in Å⁻²

Batch calculation

Use calculate_xray_properties for multiple materials at once. This uses multi-threading when Julia is started with multiple threads (julia --threads=4):

formulas  = ["SiO2", "Al2O3", "Fe2O3", "Au"]
energies  = collect(1.0:0.1:20.0)
densities = [2.2, 3.95, 5.24, 19.3]

results = calculate_xray_properties(formulas, energies, densities)

# Access by index (same order as input formulas)
sio2 = results[1]   # SiO2
au   = results[4]   # Au

println("Au critical angle at 8 keV: ", au.critical_angle[71])

Input constraints

Parameter	Constraint
Formula	Case-sensitive: `"CO"` = Carbon Monoxide, `"Co"` = Cobalt
Energy	Must be in range 0.03 – 30.0 keV
Density	Positive `Float64` in g/cm³
Formula count	Must match density count in batch mode

Chemical formula syntax

The parser supports:

Formula	Interpretation
`"SiO2"`	1 Si + 2 O
`"Al2O3"`	2 Al + 3 O
`"CaCO3"`	1 Ca + 1 C + 3 O
`"Ca(OH)2"`	Parenthesized groups: 1 Ca + 2 O + 2 H
`"Ca3(PO4)2"`	Nested groups: 3 Ca + 2 P + 8 O
`"Fe((OH)2)3"`	Deeply nested: 1 Fe + 6 O + 6 H
`"H0.5He0.5"`	Fractional stoichiometry
`"C100H200"`	Large subscripts

Multi-threading

For best batch performance, start Julia with multiple threads:

julia --threads=auto   # Uses all available cores
julia --threads=4      # Fixed 4 threads

The batch function pre-populates element caches on the main thread, then distributes formula calculations across threads using dynamic scheduling.

Memory management

For long-running applications processing many materials, clear the element cache periodically:

XRayLabTool.clear_caches!()