# Application of Intensity Ratios to Disentangle Rotational Spectra of Large Molecular Clusters: Trifluoroethylene with up to 6 CO2 Molecules

## TL;DR

This paper introduces a method using intensity ratios to analyze rotational spectra of large molecular clusters, specifically trifluoroethylene with CO2 molecules.

## Contribution

The novel contribution is a generalizable intensity ratio analysis method for deconvolving rotational spectra of mixed molecular clusters.

## Key findings

- The method identified nine TFE/CO2 clusters with m = 1−2 and n = 1−6.
- Intensity ratios correlated with cluster size and formula, enabling data benchmarking for computational methods.

## Abstract

A generalizable
method of intensity ratio analysis has
facilitated
identification and deconvolution of rotational spectra for nine mixed
trifluoroethylene (TFE)/CO2 clusters, (TFE)
m
(CO2)
n
, within
a single spectroscopic data set. Molecular complexes with m = 1−2 and n = 1−6 have
been investigated using chirped-pulse (CP) Fourier-transform microwave
(FTMW) spectroscopy. Collection of two spectra with different CO2 concentrations allowed determination of intensity ratios
of rotational transitions, which were then correlated with cluster
size and formula. The wide composition range of observed TFE/CO2 clusters provides an abundance of data with which to benchmark
computational methods for determining compositions and energy ordering
of large mixed clusters. Initial computational structural results
for experimentally observed species are also presented.