Fragmentation of Water Clusters Formed in Helium Nanodroplets by Charge Transfer and Penning Ionization

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: De, S., Abid, A. R., Asmussen, J. D., Ltaief, L. Ben, Sishodia, K., Ulmer, A., Pedersen, H. B., Krishnan, S. R., Mudrich, M.
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866910295315709952
author De, S.
Abid, A. R.
Asmussen, J. D.
Ltaief, L. Ben
Sishodia, K.
Ulmer, A.
Pedersen, H. B.
Krishnan, S. R.
Mudrich, M.
author_facet De, S.
Abid, A. R.
Asmussen, J. D.
Ltaief, L. Ben
Sishodia, K.
Ulmer, A.
Pedersen, H. B.
Krishnan, S. R.
Mudrich, M.
contents Helium nanodroplets ("HNDs") are widely used for forming tailor-made clusters and molecular complexes in a cold, transparent, and weakly-interacting matrix. Characterization of embedded species by mass spectrometry is often complicated by fragmentation and trapping of ions in the HNDs. Here, we systematically study fragment ion mass spectra of HND-aggregated water and oxygen clusters following their ionization by charge transfer ionization ("CTI") and Penning ionization ("PEI"). While the efficiency of PEI of embedded clusters is lower than for CTI by about factor 10, both the mean sizes of detected water clusters and the relative yields of unprotonated cluster ions are significantly larger, making PEI a ``soft ionization'' scheme. However, the tendency of ions to remain bound to HNDs leads to a reduced detection efficiency for large HNDs containing $>10^4$ helium atoms. These results are instrumental for determining optimal conditions for mass spectrometry and photoionization spectroscopy of molecular complexes and clusters aggregated in HNDs.
format Preprint
id arxiv_https___arxiv_org_abs_2401_06527
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Fragmentation of Water Clusters Formed in Helium Nanodroplets by Charge Transfer and Penning Ionization
De, S.
Abid, A. R.
Asmussen, J. D.
Ltaief, L. Ben
Sishodia, K.
Ulmer, A.
Pedersen, H. B.
Krishnan, S. R.
Mudrich, M.
Atomic and Molecular Clusters
Helium nanodroplets ("HNDs") are widely used for forming tailor-made clusters and molecular complexes in a cold, transparent, and weakly-interacting matrix. Characterization of embedded species by mass spectrometry is often complicated by fragmentation and trapping of ions in the HNDs. Here, we systematically study fragment ion mass spectra of HND-aggregated water and oxygen clusters following their ionization by charge transfer ionization ("CTI") and Penning ionization ("PEI"). While the efficiency of PEI of embedded clusters is lower than for CTI by about factor 10, both the mean sizes of detected water clusters and the relative yields of unprotonated cluster ions are significantly larger, making PEI a ``soft ionization'' scheme. However, the tendency of ions to remain bound to HNDs leads to a reduced detection efficiency for large HNDs containing $>10^4$ helium atoms. These results are instrumental for determining optimal conditions for mass spectrometry and photoionization spectroscopy of molecular complexes and clusters aggregated in HNDs.
title Fragmentation of Water Clusters Formed in Helium Nanodroplets by Charge Transfer and Penning Ionization
topic Atomic and Molecular Clusters
url https://arxiv.org/abs/2401.06527