\(\renewcommand\AA{\text{Å}}\)

Crystal structure

periodictable.crystal_structure

Crystal structure data.

Adds crystal_structure to the periodic table. Each crystal structure is a dictionary which contains the key ‘symmetry’. Depending on the value of crystal_structure[‘symmetry’], one or more parameters ‘a’, ‘c/a’, ‘b/a’, ‘d’, and ‘alpha’ may be present according to the following table:

Crystal lattice parameters

Symmetry

Parameters

atom

diatom

d

BCC

a

fcc

a

hcp

c/a, a

Tetragonal

c/a, a

Cubic

a

Diamond

a

Orthorhombic

c/a, a, b/a

Rhombohedral

a, alpha

SC

a

Monoclinic

Example:

>>> import periodictable as elements
>>> print(elements.C.crystal_structure['symmetry'])
Diamond
>>> print(elements.C.crystal_structure['a'])
3.57

This data is from Ashcroft and Mermin.

periodictable.crystal_structure.init(table, reload=False)

Add crystal_structure field to the element properties.