Accelerated 2D-IR Using Compressed Sensing

A fundamental aspect of Fourier transform (FT) spectroscopy is the inverse relationship between frequency resolution and the maximum scanned time delay. In situations where essential chemical information is contained in spectral peak amplitudes rather than in their detailed shapes, it is possible to dramatically reduce the experimental acquisition time of time domain methods such as two-dimensional infrared (2D-IR) spectroscopy. By introducing compressed sensing to the analysis and experimental design of 2D-IR spectroscopy, we show that waiting-time-dependent 2D peak amplitudes reproduce conventional FT acquisition and analysis but can be recorded in a fraction of the time. Peak amplitude data are often sufficient for measuring intramolecular vibrational redistribution, vibrational coherence, chemical exchange, population, and orientational relaxation, as well as spectral diffusion.