TY - JOUR
T1 - Experimental and Theoretical Study on Electron Ionization and Fragmentation of Propylene Oxide─the First Chiral Molecule Detected in the Interstellar Medium
AU - Rodrigues, Rodrigo
AU - Bou Debes, Daniel
AU - Mendes, Mónica
AU - Guerra, Pedro
AU - Mestre, Gonçalo
AU - Eden, Samuel
AU - Cornetta, Lucas M.
AU - Ingólfsson, Oddur
AU - da Silva, F. Ferreira
N1 - Funding Information:
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDP%2F00068%2F2020/PT#
F.d.S. also acknowledges the BIOSPHERE project. The project 21GRD02 BIOSPHERE has received funding from the European Partnership on Metrology (Funder ID: 10.13039/100019599), cofinanced from the European Union\u2019s Horizon Europe Research and Innovation Programme and by the Participating States. S.E. acknowledges the British EPSRC\u2019s support through a Life Sciences Interface Fellowship (EP/E039618/1), a Career Acceleration Fellowship (EP/J002577/1), and a Research Grant (EP/L002191/1). L.M.C. acknowledges the FAPESP funding agency under process no. 2020/04822-9. D.B.D. acknowledges the Sir John and Lady Mason Academic Trust for supporting his contributions to experiments in Lisbon. O.I. and F.d.S. acknowledge the COST Action CA20129 \u2033Multiscale Irradiation and Chemistry Driven Processes and Related Technologies\u2033 for the financial support to visit the University of Iceland.
Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/6/20
Y1 - 2024/6/20
N2 - Propylene oxide, CH3CHOCH2, is the first chiral molecule detected in space and the third C3 oxide detected toward the Sagittarius B2 (Sgr B2 (N)) molecular cloud, the others being propanal, CH3CH2CHO, and acetone, (CH3)2CO. With homochirality being ubiquitous in the building blocks of living matter, the formation and decay paths of propylene oxide in space are of specific interest. Motivated by the significant role of photo- and secondary electrons in astrochemistry, we have studied electron ionization and fragmentation of propylene oxide. Ion appearance energies are determined and compared to threshold values for the respective processes calculated at the G4MP2 level of theory, and potential reaction pathways are computed at the DFT level of theory. Electron ionization is found to destabilize propylene oxide, leading to barrierless opening of the C1-C2 bond of the epoxy ring, hydrogen transfer, and fragmentation over the methyl vinyl ether or rupture of the C2-O bond of the epoxy ring and fragmentation of the allyl alcohol cation as an intermediate, rather than direct bond ruptures.
AB - Propylene oxide, CH3CHOCH2, is the first chiral molecule detected in space and the third C3 oxide detected toward the Sagittarius B2 (Sgr B2 (N)) molecular cloud, the others being propanal, CH3CH2CHO, and acetone, (CH3)2CO. With homochirality being ubiquitous in the building blocks of living matter, the formation and decay paths of propylene oxide in space are of specific interest. Motivated by the significant role of photo- and secondary electrons in astrochemistry, we have studied electron ionization and fragmentation of propylene oxide. Ion appearance energies are determined and compared to threshold values for the respective processes calculated at the G4MP2 level of theory, and potential reaction pathways are computed at the DFT level of theory. Electron ionization is found to destabilize propylene oxide, leading to barrierless opening of the C1-C2 bond of the epoxy ring, hydrogen transfer, and fragmentation over the methyl vinyl ether or rupture of the C2-O bond of the epoxy ring and fragmentation of the allyl alcohol cation as an intermediate, rather than direct bond ruptures.
UR - http://www.scopus.com/inward/record.url?scp=85196027248&partnerID=8YFLogxK
U2 - 10.1021/acs.jpca.4c02116
DO - 10.1021/acs.jpca.4c02116
M3 - Article
C2 - 38860325
AN - SCOPUS:85196027248
SN - 1089-5639
VL - 128
SP - 4795
EP - 4805
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 24
ER -