INFRARED SPECTRA OF ACETONITRILE AND ACETONITRILE-D3

The infrared spectra of acetonitrile and acetonitrile-d3 have been studied at − 50°C for the high-temperature [formula omitted] crystalline phase and at − 65°, − 115° and − 192°C for the low-temperature [formula omitted] crystalline phase. A powder x-ray pattern obtained at liquid-nitrogen temperature indicates that the unit cell is primitive orthorhombic and that it contains eight molecules. It is shown that the consideration of all available structural data together with the site group and factor group splittings for the [formula omitted] crystal tends to favor [formula omitted] and [formula omitted] as possible space groups. © 1968, American Institute of Physics. All rights reserved.