Infrared Spectrum of Matrix-Isolated Hexamethylenetetramine in Ar and H2O at Cryogenic Temperatures

摘要

Laboratory infrared spectra of organic molecules taken under appropriate astrophysical conditions (low temperature, high vacuum, and frozen into mixed molecular ices) are essential for the assignment of spectral bands caused by organic species in the spectra of comets and dust in the interstellar medium. Unfortunately, few complex organic molecules have been studied under conditions relevant to astronomy. HexaMethyleneTetramine (HMT), C6Hl2N4, has been known for over 130 years. It was the first organic molecule on which X-ray crystallography was performed, and it was found to have tetrahedral symmetry. The InfRared (IR) and Raman spectra of the solid and infrared spectra of the gas have been reported, and the small number of observed fundamentals is indicative of the high degree of symmetry of this molecule. The IR spectral properties and photochemistry of HMT, especially frozen in H20 ice, are of astronomical interest, as it may comprise a portion of interstellar ice grains, icy satellites, and the organic crust of comets.