  The enriched finite element basis -- wherein the finite element basis is
enriched with atom-centered numerical functions -- has recently been shown to
be a computationally efficient basis for systematically convergent all-electron
DFT ground-state calculations. In this work, we present the expressions to
compute variationally consistent ionic forces and stress tensor for
all-electron DFT calculations in the enriched finite element basis. In
particular, we extend the formulation of configurational forces in Motamarri &
Gavini (Phys. Rev. B 2018) to the enriched finite element basis and elucidate
the additional contributions arising from the enrichment functions. We
demonstrate the accuracy of the formulation by comparing the computed forces
and stresses for various benchmark systems with those obtained from
finite-differencing the ground-state energy. Further, we also benchmark our
calculations against Gaussian basis for molecular systems and against the
LAPW+lo basis for periodic systems.
