Note that "C2h" is the symmetry[1] and "N6" is the chemical formula. Yes, 6 Nitrogen in a line, N-N-N-N-N-N with some weird bounds and internal charges, probably a good candidate to "Things I Won't Work With" in https://www.science.org/blogs/pipeline From the article:
> Detonation calculation details
[1] See for example another molecule with a different shape but the same symmetry in https://www.cup.uni-muenchen.de/ch/compchem/geom/sym_C2h.htm...