Predicting Partners

See allHide authors and affiliations

Science  29 Sep 2000:
Vol. 289, Issue 5488, pp. 2243
DOI: 10.1126/science.289.5488.2243c

Classic association species are formed from two radical species held together by weak covalent bonding. One such species found in the atmosphere is peroxyacetyl nitrate, which is very stable and thus can transport otherwise reactive radicals over long distances. Aloisio and Francisco have performed ab initio calculations of two representatives of a different class of association species, namely cyclic complexes of a radical and a molecule held together by strong hydrogen bonding. The authors find that both hydroperoxy-formic acid and hydroperoxy-acetic acid approach the stability of peroxyacetyl nitrate. These complexes are rare examples of systems whose hydrogen-bond strength is of the magnitude of weak, covalently bonded systems. These complexes also may be of importance in the atmosphere, particularly in colder regions of the troposphere where they may act as precursors to organic aerosols. — JU

J. Am. Chem. Soc., in press.

Navigate This Article