X-ray module¶

The xray module offers the following routines to access x-ray tabulated data:

Function	Description
`edge_energy()`	Returns the x-ray edge energy for a given element.
`nearest_edge()`	Returns nearest x-ray edge for a given energy.

Absorption edge energies are taken from data compiled by Elam et al. 1

References

1: W.T. Elam, B.D. Ravel, J.R. Sieber (2002) “A new atomic database for X-ray spectroscopic calculations”, Radiation Physics and Chemistry 63(2): pp 121-128, DOI:10.1016/S0969-806X(01)00227-4.

araucaria.xrdb.xray.edge_energy(sym, edge='K')[source]¶

Returns the x-ray edge energy for a given element.

Parameters

sym (str) – Atomic symbol.
edge (str) – Absorption edge in Siegbanh notation. The default is ‘K’.

Return type

float

Returns

X-ray edge energy in eV.

Raises

NameError – If sym is not available.
NameError – If edge is not available for a given sym.

Example

>>> from araucaria.xrdb import edge_energy
>>> syms = ['Fe', 'Cu', 'Zn', 'As']
>>> for s in syms:
...     energy = edge_energy(s, edge='K')
...     print('{0:2} K-edge: {1:7} eV'.format(s, energy))
Fe K-edge:  7112.0 eV
Cu K-edge:  8979.0 eV
Zn K-edge:  9659.0 eV
As K-edge: 11867.0 eV

araucaria.xrdb.xray.nearest_edge(energy)[source]¶

Return nearest x-ray edge for a given energy.

Parameters

energy (float) – X-ray energy in eV.

Return type

Tuple[str, str]

Returns

Absorption element.
Absorption edge.

Raises

ValueError – If energy is not a number.

Example

>>> from araucaria.xrdb import nearest_edge
>>> energies = [7115, 8980, 9660, 11870]
>>> for ener in energies:
...     print(nearest_edge(ener))
('Fe', 'K')
('Cu', 'K')
('Zn', 'K')
('As', 'K')