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Title: Modelling the insertion of O(1D) into methane on the surface of interstellar ice mantles
ABSTRACT The detection of many complex organic molecules (COMs) in interstellar space has sparked the study of their origins. While the formation of COMs detected in hot cores is attributed to photochemistry on warming grain surfaces followed by recombination of radicals and desorption, the formation routes in colder regions are still a debated issue with a number of theories such as cosmic ray bombardment on interstellar ice mantles or non-diffusive surface chemistry. Here, we present another method with reactions involving metastable atomic oxygen in the O(1D) state, which is initially produced by photodissociation of oxygen-containing species in interstellar ices. As a first example, we study the reactions of metastable oxygen atoms and methane in ices to form both formaldehyde and methanol. The reaction is studied incorporating two different surface processes: diffusive and non-diffusive chemistry. The formation of methanol and formaldehyde via metastable oxygen atoms is compared with well-known formation routes of both to understand the O(1D) contributions at different temperatures.  more » « less
Award ID(s):
1906489
NSF-PAR ID:
10338580
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
508
Issue:
1
ISSN:
0035-8711
Page Range / eLocation ID:
1526 to 1532
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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