Hydrogen cyanide in nitrogen-rich atmospheres of rocky exoplanets

@article{Rimmer2019HydrogenCI,
  title={Hydrogen cyanide in nitrogen-rich atmospheres of rocky exoplanets},
  author={Paul B. Rimmer and Sarah Rugheimer},
  journal={Icarus},
  year={2019}
}
Abstract Hydrogen cyanide (HCN) is a key feedstock molecule for the production of life's building blocks. The formation of HCN in an N2-rich atmospheres requires first that the triple bond between N≡N be severed, and then that the atomic nitrogen find a carbon atom. These two tasks can be accomplished via photochemistry, lightning, impacts, or volcanism. The key requirements for producing appreciable amounts of HCN are the free availability of N2 and a local carbon to oxygen ratio of C/O ≥ 1… 

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References

SHOWING 1-10 OF 70 REFERENCES
Photochemistry of methane and the formation of hydrocyanic acid (HCN) in the Earth's early atmosphere
The photochemistries of methane and HCN are discussed in the context of the primitive terrestrial atmosphere, using a detailed numerical model. In the absence of abundant O2, absorption of solar EUV
High Energy Radical Chemistry Formation of HCN-rich Atmospheres on early Earth
TLDR
Using continuously scanning time–resolved spectrometry, this work has detected ·CN radical and excited CO as the initially most abundant products in starting mixtures representative of various atmosphere-impactor volatile combinations.
Photochemistry in Terrestrial Exoplanet Atmospheres. III. Photochemistry and Thermochemistry in Thick Atmospheres on Super Earths and Mini Neptunes
Some super Earths and mini Neptunes will likely have thick atmospheres that are not H_2-dominated. We have developed a photochemistry-thermochemistry kinetic-transport model for exploring the
The atmospheric chemistry of hydrogen cyanide (HCN)
Since 1981, three groups have reported spectroscopic detections and measurements of hydrogen cyanide in the atmosphere. HCN concentrations (volume mixing ratios) of (1.5–1.7) × 10−10 appear to
Rates of fixation by lightning of carbon and nitrogen in possible primitive atmospheres
TLDR
A thermochemical-hydrodynamic model of the production of trace species by electrical discharges has been used to estimate the rates of fixation of C and N by lightning in the primitive atmosphere and reveals that the prime species produced were probably HCN and NO.
A Chemical Kinetics Network for Lightning and Life in Planetary Atmospheres
There are many open questions about prebiotic chemistry in both planetary and exoplanetary environments. The increasing number of known exoplanets and other ultra-cool, substellar objects has
STABILITY OF CO2 ATMOSPHERES ON DESICCATED M DWARF EXOPLANETS
We investigate the chemical stability of CO_2-dominated atmospheres of desiccated M dwarf terrestrial exoplanets using a one-dimensional photochemical model. Around Sun-like stars, CO_2 photolysis by
Fluxes of volatiles (H2O, CO2, N2, Cl, F) from arc volcanoes
This review gives an overview of the estimates of volatile emissions from arc and mid-ocean ridge volcanoes to the atmosphere and hydrosphere with particular focus on H2O, CO2, N2, Cl and F. The gas
A Consistent Reduced Network for HCN Chemistry in Early Earth and Titan Atmospheres: Quantum Calculations of Reaction Rate Coefficients.
TLDR
CVT using energies computed with density functional theory as a feasible and accurate method for calculating a large network of rate coefficients of small-molecule reactions is presented.
Ingassing, Storage, and Outgassing of Terrestrial Carbon through Geologic Time
Earth is unique among the terrestrial planets in our solar system in having a fluid envelope that fosters life. The secrets behind Earth’s habitable climate are well-tuned cycles of carbon (C) and
...
1
2
3
4
5
...