Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002apj...564..792d&link_type=abstract
The Astrophysical Journal, Volume 564, Issue 2, pp. 792-802.
Astronomy and Astrophysics
Astronomy
7
Stars: Circumstellar Matter, Ism: Clouds, Ism: Molecules, Molecular Processes, Stars: Individual: Alphanumeric: Irc +10216, Stars: Winds, Outflows
Scientific paper
We report calculated rate coefficients for the radiative association reactions of M+ (Na+, Mg+, or Al+) with cyanopolyynes HC2n+1N (n=0-4) and polyynes HC2nH (n=1-5), at temperatures relevant to conditions within dense interstellar clouds and the outer envelopes of mass-losing stars. These reaction rate coefficients were determined via variational transition state theory kinetic modeling calculations employing structural, energetic, and spectroscopic parameters obtained from density functional theory calculations. We have performed simple kinetic modeling of these reactions within a cold dark cloud (TMC-1) and within the outer envelope of a C-rich, post-asymptotic giant branch mass-losing star (IRC +10216), with molecular compositions and other parameters of these environments taken from current chemical models. This modeling indicates that the highly efficient radiative association reactions of Mg+ and Al+ with HC5N and HC7N, and of Na+ with HC7N, give a drastic reduction in the lifetime of the atomic metal ions in these environments compared with a model in which radiative recombination of M+ with e- is the sole metal-ion loss process. These results also provide further support to the hypothesis that M+/cyanopolyyne reactions are the route to metal cyanide radicals such as MgCN and MgNC in cold astrophysical environments.
Dunbar Robert C.
Petrie Simon
No associations
LandOfFree
Interstellar and Circumstellar Reaction Kinetics of Na+, Mg+, and Al+ with Cyanopolyynes and Polyynes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Interstellar and Circumstellar Reaction Kinetics of Na+, Mg+, and Al+ with Cyanopolyynes and Polyynes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interstellar and Circumstellar Reaction Kinetics of Na+, Mg+, and Al+ with Cyanopolyynes and Polyynes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1086930