Infrared Band Strengths and Other Properties of Amorphous and Crystalline Dimethyl Ether

Laboratory astrochemists have generated infrared (IR) data for nearly all common classes of organic compounds, but ethers in the solid phase continued to be neglected despite detections of ethers in the interstellar medium by radio astronomers and uncertainty in how extraterrestrial ethers are formed. To address this paucity of data, here we present new mid-IR spectra of amorphous and crystalline dimethyl ether, (CH3)2O, the simplest member of its class. Spectral positions are tabulated and compared to previous results, but more importantly we also report IR band strengths and absorption coefficients, which we have not found in the literature and on which quantitative IR studies depend. Optical constants of amorphous and crystalline dimethyl ether also have been calculated. Some applications are described.