Phase stability of alcohols
Highly symmetric molecules tightly fit into crystal lattices, give high melting points for their composition.  Their small surface areas minimize London dispersion forces and van der Walls forces, giving high volatility.  They tend to sublime.  Compare mp and bp data for cyclohexane and benzene versus their perfluorinated derivatives. Less exotic: n-octane, iso-octane, 2,2,4-trimethylpentane, 2,2,3,3-tetramethylbutane, and cubane.  

http://en.wikipedia.org/wiki/Neopentane 
n-Pentane and isopentane versus neopentane.

Chromium, molybdenum, and tungsetn metal versus their respective hexacarbonyls.  $\ce{-SiMe3}$ and $\ce{-CF3}$ plus symmetry confer remarkable volatility.  $\ce{I(CF3)7}$ melts and boils around 0 C.  That is molecular weight 609.95 - and it has no static molecular structure (Bartell mechanism).

http://www.patentgenius.com/patent/3992424.html 
US Patent 3992424