.. xraydb documentation master file

X-ray DB: X-ray Reference Data in SQLite
========================================

.. _XrayDB Github Page:  https://github.com/xraypy/XrayDB
.. _FFAST webpage:       https://www.nist.gov/pml/data/ffast/index.cfm
.. _PDF Version of this documentation:  https://xraypy.github.io/XrayDB/xraydb.pdf
.. _XrayDB Web App (xrayabsorption.org):  https://xraydb.xrayabsorption.org/
.. _XrayDB Web App (CARS, U Chicago):  https://millenia.cars.aps.anl.gov/xraydb

XrayDB provides atomic data, characteristic X-ray energies, and X-ray cross
sections for the elements in an SQLite3 database, ``xraydb.sqlite``.  This file
can be used directly with SQLite :cite:`sqlite` or from the many programming
language that have interfaces to SQLite.  Some of the components of the
database hold arrays of numbers, which are stored as JSON-encoded strings, and
will need to be decoded from JSON to be used.

A Python module providing an interface to this database is also provided here.

The current version of the XrayDB database is **9.2**, and the
Python module is version |release|.

Values in XrayDB use the most common SI units for X-ray work: Cross sections
are in cm^2/gr, and energies are in eV.  Energy-dependent data for
cross-sections are typically most reliable between about 250 eV to about
250,000 eV.  Elements from Z=1 to 92 are supported, with some data are included
for elements between Z=93 and Z=98.


Some useful resources using this library include:

   * `XrayDB Web App (xrayabsorption.org)`_ is an interactive web applications
     to browse the data in this database and make plots of X-ray attenuation,
     scattering factors, mirror reflectivity, and more.  Data tables and python
     code to generate that data are available for many of the calculations.

   * :ref:`periodic_tables` for printable Poster-sized Periodic tables of X-ray energies.

   * `XrayDB Github Page`_ has data sources, code, development and issues.

   * `PDF Version of this documentation`_

The project began with the data from the compilation of basic atomic
properties and X-ray absorption edge energies, emission energies, and
absorption cross sections from :cite:`Elam_Ravel_Sieber`, who assembled
data from a several sources.  More data has been added from other sources.
Energy widths of core holes for excited electronic levels from
:cite:`Keski_Krause` and :cite:`Krause_Oliver`.  Elastic X-ray scattering
data, :math:`f_0(q)` is taken from :cite:`Waasmaier_Kirfel`.  Resonant
scattering cross sections :math:`f'(E)` and :math:`f''(E)` and absorption
cross sections from :cite:`Chantler` as from the `FFAST webpage`_ (but on
a finer energy grid, data from :cite:`Chantler2016`) are also included.


Table of Contents
-----------------------

.. toctree::
   :maxdepth: 3

   installation
   periodictable
   examples
   python
   overview
   dbschema
   biblio