  Recently, Tao and Mo developed a new nonempirical semilocal
exchange-correlation density functional. The exchange part of this functional
is derived from a density matrix expansion corrected to reproduce the
fourth-order gradient expansion in the slowly varying limit, while the
correlation part is based on the TPSS correlation model with a modification for
the low-density limit. In the present work, the Tao-Mo functional is assessed
by calculations on a variety of solids and jellium surfaces. This includes 22
lattice constants and bulk moduli, 7 cohesive energies, and jellium surface
exchange and correlation energies for the density parameter rs in the range
from 2 to 3 bohrs. Our calculations show that this meta-generalized gradient
approximation can yield consistently remarkable accuracy for the properties
considered here, with mean absolute errors of 0.017 {\AA} for lattice
constants, 7.0 GPa for bulk moduli, 0.08 eV for cohesive energies, and 35
erg/cm2 for surface exchange-correlation energies, substantially improving upon
existing nonempirical semilocal density functionals.
