THE INTERSTELLAR C-H STRETCHING BAND NEAR 3.4-MU-M - CONSTRAINTS ON THE COMPOSITION OF ORGANIC MATERIAL IN THE DIFFUSE ISM

The spectra of objects suffering extinction by diffuse interstellar dust contain a broad feature centered at approximately 3300 cm-1 (approximately 3.0 mum), attributed to O-H stretching vibrations, and/or a feature near 2950 cm-1 (3.4 mum) attributed to C-H stretching vibrations. The 2950 cm-1 feature can be attributed to C-H stretching vibrations in the -CH2- and -CH3 groups of a fairly complex carbonaceous material containing aliphatic functional groups.