English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/156570
COMPARTIR / IMPACTO:
Estadísticas
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:
Título

Laboratory study of methyl isocyanate ices under astrophysical conditions

AutorMaté, Belén ; Molpeceres, Germán; Timón, Vicente ; Tanarro, Isabel ; Escribano, Rafael ; Guillemin, Jean-Claude; Cernicharo, José ; Herrero, Víctor J.
Palabras claveMethods: laboratory: solid state
Techniques: spectroscopic
ISM: clouds
methods: laboratory: solid state
Fecha de publicación12-may-2017
EditorRoyal Astronomical Society
CitaciónMonthly Notices of the Royal Astronomical Society, 470: 4222–4230 (2017)
ResumenMethyl isocyanate has been recently detected in comet 67P/Churyumov–Gerasimenko (67P/CG) and in the interstellar medium. New physicochemical studies on this species are now necessary as tools for subsequent studies in astrophysics. In this work, infrared spectra of solid CH3NCO have been obtained at temperatures of relevance for astronomical environments. The spectra are dominated by a strong, characteristic multiplet feature at 2350–2250 cm−1, which can be attributed to the asymmetric stretching of the NCO group. A phase transition from amorphous to crystalline methyl isocyanate is observed at ∼90 K. The band strengths for the absorptions of CH3NCO in ice at 20 K have been measured. Deuterated methyl isocyanate is used to help with the spectral assignment. No X-ray structure has been reported for crystalline CH3NCO. Here we advance a tentative theoretical structure, based on density functional theory (DFT) calculations, derived taking the crystal of isocyanic acid as a starting point. A harmonic theoretical spectrum is then calculated for the proposed structure and compared with the experimental data. A mixed ice of H2O and CH3NCO was formed by simultaneous deposition of water and methyl isocyanate at 20 K. The absence of new spectral features indicates that methyl isocyanate and water do not react appreciably at 20 K, but form a stable mixture. The high CH3NCO/H2O ratio reported for comet 67P/CG, and the characteristic structure of the 2350–2250 cm−1 band, makes it a very good candidate for future astronomical searches.
Descripción9 pags., 5 figs., 6 tabs.
Versión del editorhttp://doi.org/10.1021/10.1093/mnras/stx1461
URIhttp://hdl.handle.net/10261/156570
DOI10.1093/mnras/stx1461
ISSN0035-8711
E-ISSN1365-2966
Aparece en las colecciones: (CFMAC-IEM) Artículos
Ficheros en este ítem:
Fichero Descripción Tamaño Formato  
2017-Mate-Laboratory study of methyl isocyanate ices under astrophysical conditions.pdf622,86 kBAdobe PDFVista previa
Visualizar/Abrir
Mostrar el registro completo
 


NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.