Activation energies and characteristic temperatures for the volatilization of several hydrogen- bonding compounds with mild to rapid heating mass spectroscopy techniques are reported. A homologous series of N-acetyl (L-alanine), methyl esters, di-through pentaalanine, show a regular increase in activation energy of 7-9 kcal/mol per alanine residue as studied by single- ion-impact tandem mass spectroscopy. The rapid heating-chemical ionization mass ...