Abstract:
We recorded one- and two-dimensional solid-state nuclear magnetic resonance
spectra of meteoric insoluble organic matter with unprecedented sensitivity and resolution
permitting us to reveal unambiguous spectroscopic fingerprints relevant to its molecular and
isotopic features. Two-dimensional 1
H-1
H and 1
H-13C correlation experiments have unveiled
the spatial proximity between aliphatic and aromatic groups proving a highly branched
character of a rigid macromolecular network composed of short aliphatic chains linking
together small aromatic units. One-dimensional 2
H and two-dimensional 1
H-2
H correlation
spectroscopy delivered evidence of significant reduction in the deuterium enrichment of
aromatic species relevant to interstellar processes, proto-planetary disk chemistry, and to
determining the origin of the meteoritic insoluble organic matter. The experimental
approach developed in this work opens new perspectives for systematic and nondestructive
analysis at the molecular level of meteoritic insoluble organic matter even with a very small
amount of sample from some particularly rare chondrites.
