  The intrinsic lattice thermal conductivity of MoS$_2$ is an important aspect
in the design of MoS$_2$-based nanoelectronic devices. We investigate the
lattice dynamics properties of MoS$_2$ by first principles calculations. The
intrinsic thermal conductivity of single-layer MoS$_2$ is calculated using the
Boltzmann transport equation for phonons. The obtained thermal conductivity
agrees well with the measurements. The contributions of acoustic and optical
phonons to the lattice thermal conductivity are evaluated. The size dependence
of thermal conductivity is investigated as well.
