TY  - JOUR
A1  - Berrah, N.
A1  - Sánchez-González, Álvaro
A1  - Jurek, Zoltan
A1  - Obaid, Razib
A1  - Xiong, H.
A1  - Squibb, R. J.
A1  - Osipov, T.
A1  - Lutman, A.
A1  - Fang, L.
A1  - Barillot, T.
A1  - Bozek, J. D.
A1  - Cryan, J.
A1  - Wolf, T. J. A.
A1  - Rolles, Daniel
A1  - Coffee, R.
A1  - Schnorr, Kirsten
A1  - Augustin, S.
A1  - Fukuzawa, Hironobu
A1  - Motomura, K.
A1  - Niebuhr, Nina Isabelle
A1  - Frasinski, L. J.
A1  - Feifel, Raimund
A1  - Schulz, Claus-Peter
A1  - Toyota, Kenji
A1  - Son, Sang-Kil
A1  - Ueda, K.
A1  - Pfeifer, T.
A1  - Marangos, J. P.
A1  - Santra, Robin
T1  - Femtosecond-resolved observation of the fragmentation of buckminsterfullerene following X-ray multiphoton ionization
JF  - Nature physics
N2  - X-ray free-electron lasers have, over the past decade, opened up the possibility of understanding the ultrafast response of matter to intense X-ray pulses. In earlier research on atoms and small molecules, new aspects of this response were uncovered, such as rapid sequences of inner-shell photoionization and Auger ionization. Here, we studied a larger molecule, buckminsterfullerene (C-60), exposed to 640 eV X-rays, and examined the role of chemical effects, such as chemical bonds and charge transfer, on the fragmentation following multiple ionization of the molecule. To provide time resolution, we performed femtosecond-resolved X-ray pump/X-ray probe measurements, which were accompanied by advanced simulations. The simulations and experiment reveal that despite substantial ionization induced by the ultrashort (20 fs) X-ray pump pulse, the fragmentation of C-60 is considerably delayed. This work uncovers the persistence of the molecular structure of C-60, which hinders fragmentation over a timescale of hundreds of femtoseconds. Furthermore, we demonstrate that a substantial fraction of the ejected fragments are neutral carbon atoms. These findings provide insights into X-ray free-electron laser-induced radiation damage in large molecules, including biomolecules.
Y1  - 2019
U6  - https://doi.org/10.1038/s41567-019-0665-7
SN  - 1745-2473
SN  - 1745-2481
VL  - 15
IS  - 12
SP  - 1279
EP  - 1301
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Xiong, Hui
A1  - Fang, Li
A1  - Osipov, Timur
A1  - Kling, Nora G.
A1  - Wolf, Thomas J. A.
A1  - Sistrunk, Emily
A1  - Obaid, Razib
A1  - Gühr, Markus
A1  - Berrah, Nora
T1  - Fragmentation of endohedral fullerene Ho3N@C-80 in an intense femtosecond near-infrared laser field
JF  - Physical review : A, Atomic, molecular, and optical physics
N2  - The fragmentation of gas phase endohedral fullerene, Ho3N@C-80, was investigated using femtosecond near-infrared laser pulses with an ion velocity map imaging spectrometer. We observed that Ho+ abundance associated with carbon cage opening dominates at an intensity of 1.1 x 10(14) W/cm(2). As the intensity increases, the Ho+ yield associated with multifragmentation of the carbon cage exceeds the prominence of Ho+ associated with the gentler carbon cage opening. Moreover, the power law dependence of Ho+ on laser intensity indicates that the transition of the most likely fragmentation mechanisms occurs around 2.0 x 10(14) W/cm(2).
Y1  - 2018
U6  - https://doi.org/10.1103/PhysRevA.97.023419
SN  - 2469-9926
SN  - 2469-9934
VL  - 97
IS  - 2
PB  - American Physical Society
CY  - College Park
ER  -