A fast Bader atomic property calculation is performed by specifying the BADER keyword in the input file. This calculation can be used for relatively big systems (hundreds of atoms). The default calculation produces atomic electron density populations, charges, density Laplacian, dipole moments and quadrupole moments.
BADER
The accuracy of this this calculation [228,229] can be determined by the standard method: the integration of the Laplacian of the electron density must vanish over the Bader atomic basins. The default output produces these integrations. The accuracy of the method can be improved by using larger integration grids. Usually the default grid suffices an average atomic integration accuracy of 10-3 a.u. (differences of milliHartree in the energies energies). For calculations of molecules with heavy atoms an integration 6 is recommended:
INTEGRATION 6
The convergence of the integration of the electron density Laplacian is not monotone but sinusoidal. So the integration of the Laplacian is not always closer to zero as a larger grid is used. So this type of Bader atomic property calculation might be considered as an approach where computational efficiency is critical and moderate accuracy is sufficient [228,229].
