Life on extrasolar planets: the persistance and stability of cyanuric acid in protoplanetary conditions

Cyanuric acid, C3N3O3H3, has been observed in protoplanetary systems and recovered from carbonaceous meteorites. By documenting the structural and chemical transitions of cyanuric acid, we can gain clues about the origins and transformation mechanisms of pre-biotic material. An understanding of the spectral properties of processed materials could be used to identify their presence on extrasolar planets, given appropriate spectra. Cyanuric acid is of special interest because it has a ring structure consisting of alternating C and N atoms. Critical biological components, such as nucleobases, incorporate these carbon-nitrogen rings. Using X-ray diffraction and FTIR spectroscopy in the diamond anvil cell, we have begun a study of the stability of cyanuric acid at room temperature and pressures up to 30 GPa. Using a third-order Birch-Murnaghan equation of state, we determine a preliminary bulk modulus of K_0 = 0.1 GPa (K'_0=5.0), for pressures up to 10 GPa. The recovered samples appear to be denser than the initial sample by a factor of 3. FTIR spectroscopy up to 30 GPa suggests the formation of N--H·sO and C--O·sH intramolecular bonds, which could be a step towards stable molecules of greater complexity.