Rotational Desorption of Ice Mantles and Complex Molecules from
  Suprathermally Rotating Dust Grains around Young Stellar Objects
  Ice mantles on dust grains play a central role in astrochemistry. Water and
complex organic molecules (COMs) are thought to first form on the ice mantles
and subsequently are released into the gas phase due to star formation
activity. However, the critical question is whether ice mantles can survive
stellar radiation when grains are being heated from $T_{d}\sim 10\rm K$ to
$\gtrsim 100$ K. In this paper, we first study the effect of suprathermal grain
rotation driven by the intense radiation of young stellar objects (YSOs) on the
ice mantles. We find that the entire ice mantles can be disrupted into small
fragments by centrifugal stress before the water ice and COMs desorb via
thermal sublimation. We then study the consequence of resulting ice fragments
and find that tiny fragments of radius $a \lesssim 10$\AA~ exhibit transient
release of COMs due to thermal spikes, whereas larger fragments can facilitate
thermal sublimation at much higher rates than from the original icy grain or
the same rate but with temperatures of $\sim 20-40$ K lower. We find that
rotational desorption is efficient for hot cores/corinos from the inner to
outer regions where the temperature drops to $T_{\rm gas}\sim 40\rm K$ and
$n_{\rm H}\sim 10^{4}\rm cm^{-3}$. We discuss the implications of this
mechanism for desorption of COMs and water ice in various environments,
including outflow cavity walls, photodissociation regions, and protoplanetary
disks. Finally, we show that very large aggregate grains can be disrupted into
individual icy grains via rotational disruption mechanism, followed by
rotational desorption of ice mantles.
