CH2D+, the Search for the Holy Grail

Abstract

CH2D+, the singly deuterated counterpart of CH3+, offers an alternative way to mediate formation of deuterated species at temperatures of several tens of K, as compared to the release of deuterated species from grains. We report a longstanding observational search for this molecular ion, whose rotational spectroscopy is not yet completely secure. We summarize the main spectroscopic properties of this molecule and discuss the chemical network leading to the formation of CH2D+, with explicit account of the ortho/para forms of H2, H3+ and CH3+. Astrochemical models support the presence of this molecular ion in moderately warm environments at a marginal level.

25 pages, 6 Figures Accepted in Journal of Physical Chemistry A. "Oka Festschrift: Celebrating 45 years of Astrochemistry"

References in corpus (6)

• Survey of ortho-H2D+(1_{1,0}-1_{1,1}) in dense cloud cores
• Elemental nitrogen partitioning in dense interstellar clouds
• Ortho-H2 and the Age of Interstellar Dark Clouds
• A line confusion limited millimeter survey of Orion KL. II: Silicon-bearing species
• Deuterium chemistry in the Orion Bar PDR - "warm" chemistry starring CH2D+
• Constraining the Environment of CH+ Formation with CH3+ Observations

Cited by in corpus (31)

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• ALMA-IMF. VII. First release of the full spectral line cubes: Core kinematics traced by DCN J=(3-2)
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• First CH${}_3$D detection in Class 0/I proto-brown dwarfs: constraints on CH${}_4$ abundances
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• First detection of deuterated methylidyne (CD) in the interstellar medium
• CHemical Evolution in MassIve star-forming COres (CHEMICO). I. Evolution of the temperature structure
• First detection of a deuterated molecule in a starburst environment within NGC 253