# Introduction

The periodictable package provides an extensible periodic table of the elements pre-populated with data important to neutron and X-ray scattering experiments. Periodic table is written entirely in Python and does not require any external libraries.

- User’s Guide
  - Periodic Table of Elements
  - Basic usage
  - Chemical Composition
  - Bundling with py2exe
  - Adding properties
  - Custom tables
  - Data Sources
  - Contributing Changes
  - License
  - Disclaimer
  - Credits
- Reference
  - Core table
  - Chemical formula operations
  - Covalent radius
  - Fundamental constants
  - Crystal structure
  - Density
  - FASTA format for DNA/RNA and amino acid sequences
  - Magnetic Form Factor
  - Mass
  - Neutron activation
  - Neutron scattering potentials
  - X-ray scattering potentials
  - X-ray scattering factor f0 calculations
  - Element plotter
  - Utility functions

# Indices and Tables

- Index
- Module Index