# What is the process by which a solid, such as iodine, changes directly to a gas?

$\text{Sublimation}$ refers to the transition: $\text{solid "rarr" gas}$
Given a good enuff vacuum, and an efficient means to heat the solid (for example, a tube furnace), sublimation can often be performed on neutral molecules and complexes. Recoveries are generally low, but that which is collected, $\text{the sublimate}$ tends to be very pure.