# Infrared attenuation due to phase change from amorphous to crystalline observed in astrochemical propargyl ether ices

Rahul, K.K., Meka, J.K., Pavithraa, S., Gorai, P., Das, A., Lo, J.-I., Sekhar, B.N. Raja, Cheng, B.-M., Janardhan, P., Bhardwaj, A., and others. (2020) Infrared attenuation due to phase change from amorphous to crystalline observed in astrochemical propargyl ether ices. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 224 . p. 117393. ISSN 1386-1425. (doi:10.1016/j.saa.2019.117393) (KAR id:78834)

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## Abstract

Astrochemical ices are known to undergo morphological changes, from amorphous to crystalline, upon warming the ice from lower (10 K) to higher temperatures. Phase changes are mostly identified by the observation of significant changes in the InfraRed (IR) spectrum, where the IR bands that are broad in the amorphous phase are narrower and split when the ice turns crystalline. To-date all the molecules that are studied under astrochemical conditions are observed to follow such a behaviour without significant attenuation in the IR wavelength. However, in this paper we report a new observation when propargyl ether ($$C_3H_3OC_3H_3$$) is warmed from the amorphous phase, at 10 K, through the phase transition temperature of 170 K, the crystalline ice being found to strongly attenuate IR photons at the mid-IR wavelengths.

Item Type: Article 10.1016/j.saa.2019.117393 Infrared spectroscopy, Interstellar medium, Propargyl ether, Phase change, Infrared attenuation Faculties > Sciences > School of Physical Sciences Nigel Mason 19 Nov 2019 10:10 UTC 16 Jul 2020 23:00 UTC https://kar.kent.ac.uk/id/eprint/78834 (The current URI for this page, for reference purposes) https://orcid.org/0000-0002-4468-8324