Molecular stopping powers and effect of chemical bonding in gaseous amine compounds

Abstract
Molecular stopping powers of methylamine, ethylamine, dimethylamine, and trimethylamine have been measured for 0.3–2.0 MeV He+ ions. A single-bonded atomic stopping power εSB(N) for nitrogen is calculated and found to be 6%–20% lower than its triple-bonded counterpart (1/2)εexpt(N2). This disagreement is quite similar to a 6%–17% difference in single- and double-bonded carbon and oxygen atomic stopping powers previously calculated. A lower stopping power peak energy is also observed for the atom in a molecular configuration of higher bond order. These trends demonstrate clearly the effect of chemical bonding upon stopping powers.