Molecular rotational resonance spectrometers for synchronized measurements and methods for using same

Abstract

Molecular rotational resonance (MRR) spectroscopy is a structurally specific, high-resolution spectroscopy technique that can identify chemical species, including enantiomers, that cannot be resolved with other analytical techniques. In an MRR spectroscopy measurement, a gas¬ phase sample is injected into a vacuum chamber, where it is excited with millimeter-wave or microwave radiation and emits a free induction pulse (FID) in response. The spectrum of the FID pulses yields information about the chemical structure of the sample. In an MRR ratiometry measurement, the sample is illuminated simultaneously by two excitation pulses at different frequencies (e.g., a broadband pulse and a narrowband pulse in different bands or narrowband pulses at different frequencies). The pulses stimulate simultaneous or overlapping FID emissions from different components of the sample. Comparing the spectra of these FID emissions yields the ratio of the components in the sample.

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