Regenerative Soot-IX: C3 as the dominant, stable carbon cluster in high pressure sooting discharges

TL;DR

This study demonstrates that C3 is the dominant, stable carbon cluster in high-pressure sooting discharges, identified through simultaneous mass and emission spectra analysis in a dual-mode graphite hollow cathode duoplasmatron ion source.

Contribution

It provides new evidence that C3 is the primary stable carbon cluster in regenerative sooting environments at high pressure, using combined spectral analysis.

Findings

C3 is the main feature in mass spectra.

C2 appears in emission spectra, indicating an excited state.

C3 remains dominant in high-pressure regenerative sooting discharges.

Abstract

Results are presented that have been obtained while operating the graphite hollow cathode duoplasmatron ion source in dual mode under constant discharge current. This dual mode operation enabled us to obtain the mass and emission spectra simultaneously. In mass spectra C3 is the main feature but C4 and C5 are also prominent, whereas in emission spectra C2 is also there and its presence shows that it is in an excited state rather than in an ionic state. These facts provide evidence that C3 is produced due to the regeneration of a soot forming sequence and leave it in ionic state. C3 is a stable molecule and the only dominant species among the carbon clusters that survives in a regenerative sooting environment at high-pressure discharges.