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Mass-correlated rotational Raman spectra with high resolution, broad bandwidth, and absolute frequency accuracy.

ABSTRACT: We present mass-correlated rotational alignment spectroscopy, based on the optical excitation of a coherent rotational quantum wave and the observation of temporal wave interferences in a mass spectrometer. Combined electronic and opto-mechanical delays increased the observation time and energy resolution by an order of magnitude compared with preceding time-domain measurements. Rotational transition frequencies were referenced to an external clock for accurate absolute frequency measurements. Rotational Raman spectra for six naturally occurring carbon disulfide isotopologues were resolved with 3 MHz resolution over a spectral range of 500 GHz. Rotational constants were determined with single-kilohertz accuracy, competitive with state-of-the-art frequency domain measurements.

SUBMITTER: Schroter C

PROVIDER: S-EPMC5960309 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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Mass-correlated rotational Raman spectra with high resolution, broad bandwidth, and absolute frequency accuracy.

Schröter Christian C Lee Jong Chan JC Schultz Thomas T

Proceedings of the National Academy of Sciences of the United States of America 20180427 20

We present mass-correlated rotational alignment spectroscopy, based on the optical excitation of a coherent rotational quantum wave and the observation of temporal wave interferences in a mass spectrometer. Combined electronic and opto-mechanical delays increased the observation time and energy resolution by an order of magnitude compared with preceding time-domain measurements. Rotational transition frequencies were referenced to an external clock for accurate absolute frequency measurements. R ...[more]

PMID: 29703755

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