Theoretical Studies of the Extraterrestrial Chemistry of Biogenic Elements and Compounds
(active through April 2006)
NASA Exobiology Program David E. Woon
Quantum Chemical Studies of Chemistry in the Atmospheres of Titan and Other Outer Solar System Bodies
(active through June 2006)
NASA Planetary Atmospheres Program David E. Woon

Molecular Research Institute has been using computational methods to investigate problems in the fields of astrochemistry, astrobiology/exobiology, and prebiotic chemistry for over 20 years. With Gilda Loew's pre-MRI contributions, the span extends back to 1971. To download a bibliography in pdf form (~80 KB), please click here. There is also a picture of the 30+ years of reprints.

The origin of life begins with the odyssey that the elements undergo between their formation in stars by fusion of hydrogen to their arrival on the surfaces of planets. In spite of the hostile conditions, chemical complexity can develop in cold interstellar clouds (nebulae), where over 100 molecular species have been discovered to date. According to the cometary hypothesis, the raw material for prebiotic evolution on Earth may have been delivered to the surface in the form of comets, which are formed when ice-covered dust particles collect together and grow into planetoid-sized masses.

One of our ongoing projects is to characterize the manner in which ice can change the behavior of chemical reactions. As an example, the reaction between ammonia and formaldehyde has a large barrier in the gas phase, much too high to be efficient at cloud temperatures of 10-20 K. But our quantum chemical calculations found that this reaction is enhanced considerably when it occurs within an ice matrix, to the extent that there is almost no barrier remaining. The water catalyzes the reaction in two ways, by directly partipating in the reaction and by generating an electrostatic field that further reduces the barrier height.

Now that we understand how ices can enhance some reactions, we can look for viable pathways to other organic molecules that could be precursors to prebiotic species. One of the most important classes of precursors are the amino acids, which are critical components of peptides and proteins.

Visit The Astrochymist website to read more about astrochemistry.