  Daubechies wavelets are a powerful systematic basis set for electronic
structure calculations because they are orthogonal and localized both in real
and Fourier space. We describe in detail how this basis set can be used to
obtain a highly efficient and accurate method for density functional electronic
structure calculations. An implementation of this method is available in the
ABINIT free software package. This code shows high systematic convergence
properties, very good performances and an excellent efficiency for parallel
calculations.
