Atmospheric molecules and high resolution infrared spectroscopy

Experiments conducted at the High resolution and Far IR beamline of the Australian Synchrotron provide IR spectra that are analysed to obtain rovibrational properties of atmospheric molecules such as dichlorodifluoromethane. Commonly known as CFC-12 or refrigerant R12, it persists in the atmosphere for 100 years and a global warming potential (GWP) 8100 times larger than CO2 makes it one of the more important anthropogenic greenhouse gases.

IR spectra can be measured for samples at room temperature or cooled to as low as 100K to facilitate the assignment of several thousand individual rovibrational lines. Constants obtained from such analyses may be used to efficiently model the complex pattern of IR absorption within the atmospheric greenhouse window. Interstellar molecules are also studied to aid in the identification of spectral lines found in radioastronomy.