Chemistry of Low Mass Substellar Objects
  "Brown dwarfs" is the collective name for objects more massive than giant planets such as Jupiter but less massive than M dwarf stars. This review gives a brief description of the classification and chemistry of low mass dwarfs. The current spectral classification of stars includes L and T dwarfs that encompass the coolest known stars and substellar objects. The relatively low atmospheric temperatures and high total pressures in substellar dwarfs lead to molecular gas and condensate chemistry. The chemistry of elements such as C, N, O, Ti, V, Fe, Cr, and the alkali elements play a dominant role in shaping the optical and infrared spectra of the "failed" stars. Chemical diagnostics for the subclassifications are described. 
Katharina Lodders, Bruce Fegley, Jr