MARVEL analysis of the measured high-resolution rovibrational spectra of C2H2

TL;DR

This paper applies the MARVEL technique to analyze high-resolution rovibrational spectra of acetylene, determining energy levels from extensive experimental data and comparing results with effective Hamiltonian models.

Contribution

It provides a comprehensive set of experimentally derived energy levels for C2H2 using MARVEL, considering ortho and para states separately, and compares these with theoretical models.

Findings

Determined 6013 ortho and 5200 para energy levels.

Analyzed 37,813 measured transitions from 61 publications.

MARVEL results show good agreement with effective Hamiltonian calculations.

Abstract

Rotation-vibration energy levels are determined for the electronic ground state of the acetylene molecule, $^{12}$C$_2$H$_2$, using the Measured Active Rotational-Vibrational Energy Levels (MARVEL) technique. 37,813 measured transitions from 61 publications are considered. The distinct components of the spectroscopic network linking ortho and para states are considered separately. The 20,717 ortho and 17,096 para transitions measured experimentally are used to determine 6013 ortho and 5200 para energy levels. The MARVEL results are compared with alternative compilations based on the use of effective Hamiltonians.