{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T09:20:11Z","timestamp":1790673611021,"version":"4.1.0"},"reference-count":40,"publisher":"AIP Publishing","issue":"11","funder":[{"DOI":"10.13039\/501100001665","name":"Agence Nationale de la Recherche","doi-asserted-by":"publisher","award":["ANR-21-CE29-0017"],"award-info":[{"award-number":["ANR-21-CE29-0017"]}],"id":[{"id":"10.13039\/501100001665","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Domaine d\u2019Interet Majeur Astrophysique et Apparition de la vie +","award":["SPIRAULI"],"award-info":[{"award-number":["SPIRAULI"]}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,3,21]]},"abstract":"<jats:p>SiCH and its cation have consistently emerged as predicted species in models of silicon chemistry within the interstellar medium, although they remain unobserved in space. Hindered by their intrinsic instability, no spectroscopic insights have been gleaned concerning the SiCH+ cation. In this study, we present experimental measurements on the SiCH+ cation through single-photon ionization spectroscopy of the SiCH radical within the 8.0\u201311.0\u00a0eV range. Gas-phase SiCH radicals were generated through chemical reactions involving CHx (x = 0\u20133) and SiHy (y = 0\u20133) within a microwave discharge flow-tube reactor. Employing a double imaging photoelectron\/photoion coincidence spectrometer on the DESIRS beamline at the SOLEIL synchrotron, we recorded mass-selected ion yield and photoelectron spectra. From the analysis of the photoelectron spectrum supported by ab\u00a0initio calculations and Franck\u2013Condon simulations, the adiabatic ionization energies for the transitions from the X2\u03a0 ground electronic state of SiCH toward the X+3\u03a3\u2212 and A+3\u03a0 electronic states of SiCH+ have been derived [8.935(6) and 10.664(6) eV, respectively, without spin\u2013orbit correction]. The contribution from the less stable isomer HSiC has been explored in our analysis and ruled out in our experiments.<\/jats:p>","DOI":"10.1063\/5.0198424","type":"journal-article","created":{"date-parts":[[2024,3,19]],"date-time":"2024-03-19T10:06:20Z","timestamp":1710842780000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":1,"title":["Experimental characterization of SiCH+<i>via<\/i> single-photon ionization of gas-phase SiCH"],"prefix":"10.1063","volume":"160","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2215-1750","authenticated-orcid":false,"given":"N. L.","family":"Chen","sequence":"first","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CNRS, Institut des Sciences Mol\u00e9culaires d\u2019Orsay 1 , F-91405 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9658-2436","authenticated-orcid":false,"given":"B.","family":"Gans","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CNRS, Institut des Sciences Mol\u00e9culaires d\u2019Orsay 1 , F-91405 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0579-9571","authenticated-orcid":false,"given":"S.","family":"Boy\u00e9-P\u00e9ronne","sequence":"additional","affiliation":[{"name":"Universit\u00e9 Paris-Saclay, CNRS, Institut des Sciences Mol\u00e9culaires d\u2019Orsay 1 , F-91405 Orsay, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3053-683X","authenticated-orcid":false,"given":"S.","family":"Hartweg","sequence":"additional","affiliation":[{"name":"Synchrotron SOLEIL, L\u2019Orme des Merisiers 2 , St. Aubin, F-91192 Gif sur Yvette, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2915-2553","authenticated-orcid":false,"given":"G. A.","family":"Garcia","sequence":"additional","affiliation":[{"name":"Synchrotron SOLEIL, L\u2019Orme des Merisiers 2 , St. Aubin, F-91192 Gif sur Yvette, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8063-8685","authenticated-orcid":false,"given":"J.-C.","family":"Loison","sequence":"additional","affiliation":[{"name":"Institut des Sciences Mol\u00e9culaires, CNRS, Universit\u00e9 de Bordeaux 3 , F-33400 Talence, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2024,3,19]]},"reference":[{"key":"2024031909461540200_c1","doi-asserted-by":"publisher","first-page":"1220","DOI":"10.1086\/375492","article-title":"Solar system abundances and condensation temperatures of the elements","volume":"591","year":"2003","journal-title":"Astrophys. J."},{"key":"2024031909461540200_c2","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1086\/162480","article-title":"Optical properties of interstellar graphite and silicate grains","volume":"285","year":"1984","journal-title":"Astrophys. J."},{"key":"2024031909461540200_c3","doi-asserted-by":"publisher","first-page":"279","DOI":"10.1146\/annurev.astro.34.1.279","article-title":"Interstellar abundances from absorption-line observations with the hubble space telescope","volume":"34","year":"1996","journal-title":"Annu. Rev. Astron. Astrophys."},{"key":"2024031909461540200_c4","doi-asserted-by":"publisher","first-page":"386","DOI":"10.1086\/155167","article-title":"The chemistry of silicon in interstellar clouds","volume":"213","year":"1977","journal-title":"Astrophys. J."},{"key":"2024031909461540200_c5","doi-asserted-by":"publisher","first-page":"509","DOI":"10.1007\/bf00639153","article-title":"Silicon chemistry in dense clouds","volume":"72","year":"1980","journal-title":"Astrophys. Space Sci."},{"key":"2024031909461540200_c6","doi-asserted-by":"publisher","first-page":"2396","DOI":"10.1021\/ja00216a010","article-title":"Gas-phase reactions of silicon ion (Si+ with ammonia and the amines (CH3)NH3\u2212x(x = 1\u20133): Possible ion-molecule reaction pathways toward SiH, SiCH, SiNH, SiCH3, SiNCH3, and H2SiNH","volume":"110","year":"1988","journal-title":"J. Am. Chem. Soc."},{"key":"2024031909461540200_c7","first-page":"205","article-title":"The chemistry of silicon in dense interstellar clouds","volume":"222","year":"1989","journal-title":"Astron. Astrophys."},{"key":"2024031909461540200_c8","doi-asserted-by":"publisher","first-page":"52","DOI":"10.1021\/ja00001a010","article-title":"Experimental evidence for the existence of SiCHx (x = 1\u20133) molecules in the gas phase","volume":"113","year":"1991","journal-title":"J. Am. Chem. Soc."},{"key":"2024031909461540200_c9","doi-asserted-by":"publisher","first-page":"545","DOI":"10.1086\/152746","article-title":"High-resolution spectra of cool stars in the 10- and 20-micron regions","volume":"188","year":"1974","journal-title":"Astrophys. J."},{"key":"2024031909461540200_c10","doi-asserted-by":"publisher","first-page":"L25","DOI":"10.1086\/185449","article-title":"Astonomical and laboratory detection of the SiC radical","volume":"341","year":"1989","journal-title":"Astrophys. J."},{"key":"2024031909461540200_c11","doi-asserted-by":"publisher","first-page":"535","DOI":"10.1017\/s1743921318005410","article-title":"Circumstellar chemistry of Si-C bearing molecules in the C-rich AGB star IRC+10216","volume":"14","year":"2018","journal-title":"Proc. Int. Astron. Union"},{"key":"2024031909461540200_c12","doi-asserted-by":"publisher","first-page":"245","DOI":"10.1016\/0168-1176(90)87014-8","article-title":"Ion\/molecule reactions in silane-carbon monoxide mixtures: Possible synthesis of the SiC radical in the electric discharge chemistry","volume":"101","year":"1990","journal-title":"Int. J. Mass Spectrom. Ion Processes"},{"key":"2024031909461540200_c13","doi-asserted-by":"publisher","first-page":"309","DOI":"10.1002\/ijch.198000038","article-title":"Ab initio MRD-CI calculations for HAB molecules I. Isomerization energies for HOS, HNP and HCSi and their positive ions","volume":"19","year":"1980","journal-title":"Isr. J. Chem."},{"key":"2024031909461540200_c14","doi-asserted-by":"publisher","first-page":"343","DOI":"10.1063\/1.46617","article-title":"MCSCF-CI study of the isomerization reaction HCSi \u2192 HSiC","volume":"312","year":"1994","journal-title":"AIP Conf. Proc."},{"key":"2024031909461540200_c15","doi-asserted-by":"publisher","first-page":"91","DOI":"10.1016\/s0009-2614(97)00086-9","article-title":"Ro-vibronic spectrum of the HCSi radical","volume":"267","year":"1997","journal-title":"Chem. Phys. Lett."},{"key":"2024031909461540200_c16","doi-asserted-by":"publisher","first-page":"3504","DOI":"10.1063\/1.475748","article-title":"Fourier transform infrared observation of the vibrational spectrum of the \u03bd1(\u03c3) mode of the linear SiCH in Ar at 10 K","volume":"108","year":"1998","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c17","doi-asserted-by":"publisher","first-page":"199","DOI":"10.1007\/pl00021570","article-title":"The optical spectrum of HCSi","volume":"2","year":"1998","journal-title":"Eur. Phys. J. D"},{"key":"2024031909461540200_c18","doi-asserted-by":"publisher","first-page":"10806","DOI":"10.1063\/1.481724","article-title":"Fourier transform emission spectrum of the HCSi radical, \u00c32\u03a3+\u2013X\u03032\u03a0i transition","volume":"112","year":"2000","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c19","doi-asserted-by":"publisher","first-page":"3662","DOI":"10.1063\/1.480518","article-title":"The electronic spectrum of silicon methylidyne (SiCH), a molecule with a silicon\u2013carbon triple bond in the excited state","volume":"112","year":"2000","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c20","doi-asserted-by":"publisher","first-page":"725","DOI":"10.1063\/1.1331316","article-title":"Orbital angular momentum (Renner\u2013Teller) effects in the 2\u03a0i ground state of silicon methylidyne (SiCH)","volume":"114","year":"2001","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c21","doi-asserted-by":"publisher","first-page":"508","DOI":"10.1107\/s0909049512010588","article-title":"DESIRS: A state-of-the-art VUV beamline featuring high resolution and variable polarization for spectroscopy and dichroism at SOLEIL","volume":"19","year":"2012","journal-title":"J. Synchrotron Radiat."},{"key":"2024031909461540200_c22","doi-asserted-by":"publisher","first-page":"123108","DOI":"10.1063\/1.4937624","article-title":"Vacuum upgrade and enhanced performances of the double imaging electron\/ion coincidence end-station at the vacuum ultraviolet beamline DESIRS","volume":"86","year":"2015","journal-title":"Rev. Sci. Instrum."},{"key":"2024031909461540200_c23","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1016\/j.elspec.2015.05.010","article-title":"Threshold photoelectron spectroscopy of the imidogen radical","volume":"203","year":"2015","journal-title":"J. Electron Spectrosc. Relat. Phenom."},{"key":"2024031909461540200_c24","doi-asserted-by":"publisher","first-page":"23568","DOI":"10.1039\/d3cp02775a","article-title":"Single-photon ionization of SiC in the gas phase: Experimental and ab\u00a0initio characterization of SiC+","volume":"25","year":"2023","journal-title":"Phys. Chem. Chem. Phys."},{"key":"2024031909461540200_c25","doi-asserted-by":"publisher","first-page":"053112","DOI":"10.1063\/1.4807751","article-title":"DELICIOUS III: A multipurpose double imaging particle coincidence spectrometer for gas phase vacuum ultraviolet photodynamics studies","volume":"84","year":"2013","journal-title":"Rev. Sci. Instrum."},{"key":"2024031909461540200_c26","doi-asserted-by":"publisher","first-page":"3334","DOI":"10.1039\/C004156B","article-title":"Biomolecular structures: From isolated molecules to the cell crowded medium","volume":"12","year":"2010","journal-title":"Phys. Chem. Chem. Phys."},{"key":"2024031909461540200_c27","doi-asserted-by":"publisher","first-page":"234309","DOI":"10.1063\/1.4972018","article-title":"Experimental and ab\u00a0initio characterization of HC3N+ vibronic structure. II. High-resolution VUV PFI-ZEKE spectroscopy","volume":"145","year":"2016","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c28","doi-asserted-by":"publisher","first-page":"4520","DOI":"10.1063\/1.465011","article-title":"Factors affecting lifetimes and resolution of Rydberg states observed in zero-electron-kinetic-energy spectroscopy","volume":"98","year":"1993","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c29","doi-asserted-by":"publisher","first-page":"242","DOI":"10.1002\/wcms.82","article-title":"Molpro: A general-purpose quantum chemistry program package","volume":"2","year":"2012","journal-title":"WIREs Comput. Mol. Sci."},{"key":"2024031909461540200_c30","doi-asserted-by":"publisher","first-page":"144107","DOI":"10.1063\/5.0005081","article-title":"The Molpro quantum chemistry package","volume":"152","year":"2020","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c31","year":"2022"},{"key":"2024031909461540200_c32","doi-asserted-by":"publisher","first-page":"5803","DOI":"10.1063\/1.455556","article-title":"An efficient internally contracted multiconfiguration\u2013reference configuration interaction method","volume":"89","year":"1988","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c33","doi-asserted-by":"publisher","first-page":"403","DOI":"10.1016\/0009-2614(77)80475-2","article-title":"Size consistency in the dilute helium gas electronic structure","volume":"52","year":"1977","journal-title":"Chem. Phys. Lett."},{"key":"2024031909461540200_c34","doi-asserted-by":"publisher","first-page":"5053","DOI":"10.1063\/1.448627","article-title":"A second order multiconfiguration SCF procedure with optimum convergence","volume":"82","year":"1985","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c35","doi-asserted-by":"publisher","first-page":"e1546","DOI":"10.1002\/wcms.1546","article-title":"The ezSpectra suite: An easy-to-use toolkit for spectroscopy modeling","volume":"12","year":"2022","journal-title":"WIREs Comput. Mol. Sci."},{"key":"2024031909461540200_c36","doi-asserted-by":"publisher","first-page":"4472","DOI":"10.1063\/1.1345512","article-title":"The X2\u03a0 and A2\u03a3+ electronic states of the HCSi radical: Characterization of the Renner\u2013Teller effect in the ground state","volume":"114","year":"2001","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c37","doi-asserted-by":"publisher","first-page":"113","DOI":"10.1016\/j.jms.2003.10.006","article-title":"Near-infrared diode laser spectroscopy of the HCSi radical","volume":"223","year":"2004","journal-title":"J. Mol. Spectrosc."},{"key":"2024031909461540200_c38","doi-asserted-by":"publisher","first-page":"204307","DOI":"10.1063\/1.4950880","article-title":"Synchrotron-based valence shell photoionization of CH radical","volume":"144","year":"2016","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c39","doi-asserted-by":"publisher","first-page":"014303","DOI":"10.1063\/5.0094863","article-title":"Photoionization spectroscopy of the SiH free radical in the vacuum-ultraviolet range","volume":"157","year":"2022","journal-title":"J. Chem. Phys."},{"key":"2024031909461540200_c40","doi-asserted-by":"publisher","first-page":"30838","DOI":"10.1039\/d3cp04244h","article-title":"Refining the thermochemical properties of CF, SiF, and their cations by combining photoelectron spectroscopy, quantum chemical calculations, and the active thermochemical tables approach","volume":"25","year":"2023","journal-title":"Phys. Chem. Chem. Phys."}],"container-title":["The Journal of Chemical Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/5.0198424\/19833612\/114310_1_5.0198424.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/5.0198424\/19833612\/114310_1_5.0198424.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,3,19]],"date-time":"2024-03-19T10:06:26Z","timestamp":1710842786000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/jcp\/article\/160\/11\/114310\/3277843\/Experimental-characterization-of-SiCH-via-single"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,3,19]]},"references-count":40,"journal-issue":{"issue":"11","published-print":{"date-parts":[[2024,3,21]]}},"URL":"https:\/\/doi.org\/10.1063\/5.0198424","relation":{},"ISSN":["0021-9606","1089-7690"],"issn-type":[{"value":"0021-9606","type":"print"},{"value":"1089-7690","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2024,3,21]]},"published":{"date-parts":[[2024,3,19]]},"article-number":"114310"}}