units

Time

1 a.u. = 0.02419 fs
intramolecular vibrational redistribution (IVR) proceeds at ps time scale. (H scattering from graphene)

Chemical accuracy

Orbital- and state-dependent functionals in density-functional theory
1 kcal/mol in binding energies
0.01 Å in bond distances
10 cm$^{−1}$ in vibrational frequencies