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  • Spectroscopic models of CO2 microsolvation: Bringing data analytics techniques to undergraduate physical chemistry research
Title: Spectroscopic models of CO2 microsolvation: Bringing data analytics techniques to undergraduate physical chemistry research
Broadband microwave spectra have been recorded for weakly bound clusters formed from mixtures containing fluoroethylene (FE) or 1,1-difluoroethylene (DFE) and varying percentages of CO2. These clusters serve as simple models for behavior of supercritical CO2 as a solvent. Analysis of changes in rotational transition intensities as CO2 concentration is systematically varied allows identification and assignment of spectra for a multitude of different clusters from within a single data set, with at least 15 species identified in FE/CO2 mixtures, and 4 species so far identified in DFE/CO2 mixtures. Several analysis approaches have been implemented, ranging from simple correlation of intensity variations between two spectra recorded with different sample concentrations, to more sophisticated principal component analysis based representations of the spectroscopic data from multiple scans. These techniques provide a range of tools that, in addition to facilitating assignment of spectra of complex mixtures, also assist in identifying the chemical species that give rise to the spectra within each mixture. The visual aspects of the research process, and the accessibility of coding tools such as Python, Excel and Mathcad, make this work particularly appropriate to undergraduate students, including those with little or no previous physical chemistry experience.  more » « less
Award ID(s):
1664900
PAR ID:
10290645
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
American Chemical Society National Meeting Fall 2021
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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