Tentative detection of HC5NH+ in TMC-1.

ABSTRACT: Using the Yebes 40m radio telescope, we report the detection of a series of seven lines harmonically related with a rotational constant B0=1295.81581 ± 0.00026 MHz and a distortion constant D0 = 27.3 ± 0.5 Hz towards the cold dense cloud TMC-1. Ab initio calculations indicate that the best possible candidates are the cations HC5NH+ and NC4NH+. From a comparison between calculated and observed rotational constants and other arguments based on proton affinities and dipole moments, we conclude that the best candidate for a carrier of the observed lines is the protonated cyanodiacetylene cation, HC5NH+. The HC5N/HC5NH+ ratio derived in TMC-1 is 240, which is very similar to the HC3N/HC3NH+ ratio. Results are discussed in the framework of a chemical model for protonated molecules in cold dense

SUBMITTER: Marcelino N 

PROVIDER: S-EPMC7116411 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature