Synthesis and Spectroscopic Characterization of Interstellar Candidate Ethynyl Thiocyanate: HCCSCN

TL;DR

This study spectroscopically characterizes the interstellar candidate molecule HCCSCN, providing its first experimental spectral data and searching for its presence in various molecular clouds.

Contribution

First experimental spectral data for HCCSCN, including ground and excited states, aiding astrophysical detection efforts.

Findings

314 spectral transitions assigned to HCCSCN

Spectroscopic constants accurately determined

Upper limits set for HCCSCN in observed molecular clouds

Abstract

This work aims to spectroscopically characterize and provide for the first time direct experimental frequencies of the ground vibrational state and two excited states of the simplest alkynyl thiocyanate (HCCSCN) for astrophysical use. Both microwave (8-16~GHz) and millimeter wave regions (50-120~GHz) of the spectrum have been measured and analyzed in terms of Watson's semirigid rotor Hamiltonian. A total of 314 transitions were assigned to the ground state of HCCSCN and a first set of spectroscopic constants have been accurately determined. Spectral features of the molecule were then searched for in Sgr B2(N), NGC 6334I, G+0.693-0.027 and TMC-1 molecular clouds. Upper limits to the column density are provided.