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Updated: May 7, 2026
09:53
Molecular Beam Mass Spectrometry With Tunable Vacuum Ultraviolet (VUV) Synchrotron Radiation
Published on: October 30, 2012
Proton ejection from molecular hydride clusters exposed to strong x-ray pulses
Pierfrancesco Di Cintio1, Ulf Saalmann, Jan-Michael Rost
1Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany.
Physical Review Letters
|October 8, 2013
Summary
Short X-ray pulses eject fast protons from hydrogen-containing clusters. This process shields heavy atoms from explosion, preserving the cluster
Area of Science:
- Atomic and molecular physics
- X-ray science
- Materials science
Background:
- Small molecules with hydrogen eject fast protons when exposed to short X-ray pulses.
- Cluster charging influences electron migration, proton segregation, and heavy atom explosion dynamics.
Purpose of the Study:
- Investigate the effect of X-ray intensity on proton dynamics and heavy atom preservation in hydride clusters.
- Systematically study the isoelectronic sequence from methane to neon.
Main Methods:
- Illumination of hydride clusters (methane, ammonia, water) with short X-ray pulses.
- Control of cluster charging via X-ray intensity.
- Analysis of proton ejection and heavy atom explosion dynamics.
Main Results:
- Controlled charging induces electron migration, segregating protons and hindering heavy atom explosion.
- The entire heavy atom backbone remains intact, unlike in core-shell systems.
- Proton dynamics are crucial for preserving cluster structure.
Conclusions:
- Hydride clusters offer a method to protect heavy atoms from X-ray-induced damage.
- Intricate proton dynamics are key to maintaining structural integrity.
- This offers a novel approach to radiation damage mitigation in molecular systems.
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