  The increasing use of high-throughput density-functional theory (DFT)
calculations in the computational design and optimization of materials requires
the availability of a comprehensive set of soft and transferable
pseudopotentials. Here we present design criteria and testing results for a new
open-source "GBRV" ultrasoft pseudopotential library that has been optimized
for use in high-throughput DFT calculations. We benchmark the GBRV potentials,
as well as two other pseudopotential sets available in the literature, to
all-electron calculations in order to validate their accuracy. The results
allow us to draw conclusions about the accuracy of modern pseudopotentials in a
variety of chemical environments.
