Fragmentation dynamics of CS2 dications and trications following S 2p ionization

F Felix Allum (Stanford PULSE Institute) C Chow-shing Lam B Benjamin Erk (Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, Hamburg 22607, Germany) H Hubertus Bromberger (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) P Philip H. Bucksbaum M Mathew Britton M Michael Burt (Chemistry Research Laboratory, Department of Chemistry) N Nagitha Ekanayake (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) I Ian Gabalski D Diksha Garg (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) E Eva Gougoula (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) D David Heathcote A Andrew J. Howard P Paul Hockett D David M. P. Holland (Daresbury Laboratory) S Sonu Kumar J Jason W. L. Lee J Joseph McManus (Chemistry Research Laboratory, Department of Chemistry, University of Oxford 4 , Oxford OX1 3TA,) J Jochen Mikosch (Institut für Physik, Universität Kassel 12 , Heinrich-Plett-Straße 40, 34132 Kassel,) D Dennis Milešević (Chemistry Research Laboratory, Department of Chemistry, University of Oxford 4 , Oxford OX1 3TA,) R Russell S. Minns (School of Chemistry and Chemical Engineering) C Christina C. Papadopoulou (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) C Christopher Passow W Weronika O. Razmus A Anja Röder (Max-Born-Institute 14 , Max-Born-Straße 2A, 12489 Berlin,) D Daniel Rolles (James R. Macdonald Laboratory, Physics Department) A Arnaud Rouzée (Max-Born-Institut, Max Born Straße 2A, Berlin 12489, Germany) M Michael S. Schuurman (National Research Council Canada) A Alcides Simao (Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150 17 , 44801 Bochum,) A Albert Stolow (Department of Chemistry and Biomolecular Sciences, University of Ottawa 1 , D’Iorio Hall, Ottawa, Ontario K1N 6N5,) A Atia-Tul Noor (Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,) J James Unwin C Claire Vallance T Tiffany Walmsley M Mark Brouard (Chemistry Research Laboratory, Department of Chemistry) R Ruaridh Forbes (Linac Coherent Light Source)

Abstract

We present the results from a detailed study of the fragmentation dynamics of CS22+ and CS23+, formed in intense femtosecond soft x-ray pulses above the sulfur 2p edge, primarily through single core photoionization from the S 2p site, and subsequent Auger–Meitner decay(s). By combining three-dimensional velocity map imaging with covariance analysis, we determine the relative momenta of the ions produced in each two- and three-body fragmentation channel, at significantly higher ion count rates than conventional coincidence measurements. We shed new light on the wide range of fragmentation channels observed from the CS2 dication and trication, including channels that involve ionization-induced bond formation and fragmentations producing undetected neutral cofragments. In the latter case, a “native frames” approach is used to isolate contributions from concerted and sequential fragmentations and extract dynamical information about each step of a concerted fragmentation process. While dications often fragment sequentially, the trication is dominated by concerted fragmentation. The main trication fragmentation channel into S+ + C+ + S+ can be well-approximated by classical Coulombic simulations of the ground-state geometry distribution, reflecting both the nature of the trication potential energy surface and the rapid multiple ionization prior to substantial structural dynamics. This study demonstrates ways in which fundamental insights into the fragmentation dynamics of polycations following x-ray ionization may be extracted, which will be beneficial to future studies that employ time-resolved x-ray Coulomb explosion imaging to study ultrafast photochemistry.

Article Details

Volume / Issue Vol. 164, Issue 2
Published January 14, 2026
ISSN 0021-9606
Publisher American Institute of Physics

Journal Info

The Journal of Chemical Physics

American Institute of Physics

ISSN: 0021-9606 Physical Sciences

Authors (36)

F

Felix Allum

Stanford PULSE Institute

C

Chow-shing Lam

B

Benjamin Erk

Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, Hamburg 22607, Germany

H

Hubertus Bromberger

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

P

Philip H. Bucksbaum

M

Mathew Britton

M

Michael Burt

Chemistry Research Laboratory, Department of Chemistry

N

Nagitha Ekanayake

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

I

Ian Gabalski

D

Diksha Garg

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

E

Eva Gougoula

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

D

David Heathcote

A

Andrew J. Howard

P

Paul Hockett

D

David M. P. Holland

Daresbury Laboratory

S

Sonu Kumar

J

Jason W. L. Lee

J

Joseph McManus

Chemistry Research Laboratory, Department of Chemistry, University of Oxford 4 , Oxford OX1 3TA,

J

Jochen Mikosch

Institut für Physik, Universität Kassel 12 , Heinrich-Plett-Straße 40, 34132 Kassel,

D

Dennis Milešević

Chemistry Research Laboratory, Department of Chemistry, University of Oxford 4 , Oxford OX1 3TA,

R

Russell S. Minns

School of Chemistry and Chemical Engineering

C

Christina C. Papadopoulou

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

C

Christopher Passow

W

Weronika O. Razmus

A

Anja Röder

Max-Born-Institute 14 , Max-Born-Straße 2A, 12489 Berlin,

D

Daniel Rolles

James R. Macdonald Laboratory, Physics Department

A

Arnaud Rouzée

Max-Born-Institut, Max Born Straße 2A, Berlin 12489, Germany

M

Michael S. Schuurman

National Research Council Canada

A

Alcides Simao

Ruhr-Universität Bochum, Fakultät für Chemie und Biochemie, Organische Chemie II, Universitätsstraße 150 17 , 44801 Bochum,

A

Albert Stolow

Department of Chemistry and Biomolecular Sciences, University of Ottawa 1 , D’Iorio Hall, Ottawa, Ontario K1N 6N5,

A

Atia-Tul Noor

Deutsches Elektronen-Synchrotron DESY 1 , Notkestr. 85, 22607 Hamburg,

J

James Unwin

C

Claire Vallance

T

Tiffany Walmsley

M

Mark Brouard

Chemistry Research Laboratory, Department of Chemistry

R

Ruaridh Forbes

Linac Coherent Light Source