ASE Manual Release 3.6.1.2825 CAMd - CampOS Wiki

data.cpk_colors
data.reference_states
data.vdw_radii
All of these are lists that should be indexed with an atomic number:
>>> from ase.data import *
>>> atomic_names[92]
’Uranium’
>>> atomic_masses[2]
4.0026000000000002
data.atomic_numbers
ASE Manual, Release 3.6.1.2828
If you don’t know the atomic number of some element, then you can look it up in the atomic_numbers
dictionary:
>>> atomic_numbers[’Cu’]
29
>>> covalent_radii[29]
1.1699999999999999
The covalent radii are taken from [Cordeo08]. The source of the van der Waals radii is given in vdw.py.
7.24.2 Molecular data
The G1, G2, and G3-databases are available in the molecules module.
Example:
>>> from ase.data.molecules import molecule
>>> atoms = molecule(’H2O’)
All molecular members of each database is conveniently contained in a list of strings (g1, g2, g3), and one can
look up the experimental atomization energy for each molecule. This is extrapolated from experimental heats of
formation at room temperature, using calculated zero-point energies and thermal corrections.
Example:
>>> from ase.data.molecules import molecule, g2, get_atomization_energy
>>> g2[11]
’H2O’
>>> atoms = molecule(g2[11])
>>> get_atomization_energy(g2[11])
232.57990000000001
>>> from ase.units import kcal,mol
>>> get_atomization_energy(g2[11])*kcal/mol
10.08562144637833
where the last line converts the experimental atomization energy of H2O from units of kcal/mol to eV.
7.24.3 S22, s26, and s22x5 data
The s22, s26, and s22x5 databases are available in the s22 module.
Each weakly bonded complex is identified as an entry in a list of strings (s22, s26, s22x5), and is fully created by
a ‘create’-function:
>>> from ase.data.s22 import s22, create_s22_system
>>> sys = s22[0]
>>> sys
’Ammonia_dimer’
7.24. The data module 167