Untitled

Abstract

Hydrogen cyanide polymers form spontaneously from HCN and traces of base catalysts. It is probable that these polymers played an important role in the early stages of chemical evolution. Nevertheless, their full structural characterization has still not been accomplished. A number of mass spectrometric methods have now been applied to this structural problem including FAB-MS, thermal desorption EI-MS, ESI-MS, APCI-MS and off-line TMAH thermochemolysis/GC-MS. This latter method causes bond cleaveage and in situ methylation producing a suite of products which provides valuable insight into the substructural features of HCN polymers and also promises to serve as a sensitive diagnostic tool for detecting the presence of HCN polymers in samples from diverse sources.

HCN polymers characterized by solid state NMR: Chains and sheets formed in the neat liquid

“…It is also the case that saturated cyclic structures potentially derivative from the polymer in Fig. 7͑b͒ have been reported by Minard et al 7 Chemical shifts lead to the same structures. Polymer signals are observed at 180-150 and 100-70 ppm for 13 C and 270-180, 108, 82, and 61 ppm for 15 N. Strikingly absent are some of the signals predicted for ladder polymers ͑see legend of Fig.…”

“…However, the structures of these polymers remain unknown despite extensive effort. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Figures 1 and 2 show the proposed polymer structures. The "ladder" structures in Fig.…”

VUV photophysics and dissociative photoionization of pyrimidine, purine, imidazole and benzimidazole in the 7–18eV photon energy range

“…Combining the results with other observations led to the conclusion that the molecular gas phase ions observed, which include relatively small ions containing nitrogen, are derived from larger polymers present in the cometary matter [98]. More recently, pyrolysis-GC-MS has been applied to analyse HCN-polymers which may be among the organic macromolecules most readily formed within the solar system [99]. These polymers can form spontaneously from HCN in the presence of trace quantities of base catalysts.…”

ICE CHEMISTRY ON OUTER SOLAR SYSTEM BODIES: ELECTRON RADIOLYSIS OF N2-, CH4-, AND CO-CONTAINING ICES

“…This paper focuses on the properties of the refractory residues that result from these irradiation experiments using multiple analytical techniques, including FTIR spectroscopy (mid-and near-IR regions, from 7000 to 600 cm −1 , 1.43-16.7 μm), X-ray absorption near-edge structure (XANES) spectroscopy, and gas chromatography coupled with mass spectroscopy (GC-MS). The properties of the residues from the UV-and e − -irradiated ices are also compared to samples of poly-HCN provided by Bob Minard (Minard et al 1998) and later analyzed by Hiroshi Imanaka (Imanaka & Smith 2010). Poly-HCN has been suggested as a possible component of the refractory carbonaceous material found on comets and on the surfaces of objects in the outer Solar System (e.g., Cruikshank et al 1991;Matthews 1992) and has been previously compared to Titan-like tholins produced in the laboratory (Vuitton et al 2010).…”