Interstellar Alcohols

Abstract

We have investigated the gas-phase chemistry in dense cores where ice mantles containing ethanol and other alcohols have been evaporated. Model calculations show that methanol, ethanol, propanol, and butanol drive a chemistry leading to the formation of several large ethers and esters. Of these molecules, methyl ethyl ether (CH<SUB>3</SUB>OC<SUB>2</SUB>H<SUB>5</SUB>) and diethyl ether [(C<SUB>2</SUB>H<SUB>5</SUB>)<SUB>2</SUB>O] attain the highest abundances and should be present in detectable quantities within cores rich in ethanol and methanol. Gas-phase reactions act to destroy evaporated ethanol and a low observed abundance of gas-phase C<SUB>2</SUB>H<SUB>5</SUB>OH does not rule out a high solid-phase abundance. Grain surface formation mechanisms and other possible gas-phase reactions driven by alcohols are discussed, as are observing strategies for the detection of these large interstellar molecules.