English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Complex Organic Molecules (COMs) have been detected in the interstellarmedium (ISM). However, it is not clear whether their synthesis occurs on theicy surfaces of interstellar grains or via a series of gas-phase reactions. Asa test case of the COMs synthesis in the ISM, we present new quantum chemicalcalculations on the formation of acetaldehyde (CH3CHO) from the coupling of theHCO and CH3 radicals, both in gas phase and on water ice surfaces. The bindingenergies of HCO and CH3 on the amorphous water ice were also computed (2333 and734 K, respectively). Results indicate that, in gas phase, the products couldbe either CH3CHO, CH4 + CO, or CH3OCH, depending on the relative orientation ofthe two radicals. However, on the amorphous water ice, only the CH4 + COproduct is possible due to the geometrical constraints imposed by the water icesurface. Therefore, acetaldehyde cannot be synthesized by the CH3 + HCOcoupling on the icy grains. We discuss the implications of these results andother cases, such as ethylene glycol and dimethyl ether, in which similarsituations can occur, suggesting that formation of these molecules on the grainsurfaces might be unlikely.

The (impossible?) formation of acetaldehyde on the grain surfaces: insights from quantum chemical calculations