Publications de Marcel Drabbels

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New experimental results are reported on state-dependent steric effects in NO-Ar inelastic scattering. The NO molecules are selected in the J = 1/2(-) l-doublet state of the electronic ground state and oriented relative to the incident Ar atoms. The steric asymmetry, S = (sigma(NO) - sigma(ON))/(sigma(NO) + sigma(ON)), has been measured as a function of the final rotational state J'. In a previous study, quantum-mechanical scattering calculations were found to predict strong oscillations in S, but experimen

Proteins typically undergo dynamics on the microsecond to millisecond timescale, which is much faster than the time resolution of cryo-electron microscopy. Here, we propose a novel approach for microsecond time-resolved cryo-electron microscopy that involv ...

Whereas most of the phenomena associated with superfluidity have been observed in finite-size helium systems, the nucleation of quantized vortices has proven elusive. Here we show that the solvation of a Ba+ ion created by photoionization of neutral Ba at ...

We have recently introduced a novel approach to time-resolved cryo-electron microscopy (cryo-EM) that affords microsecond time resolution. It involves melting a cryo sample with a laser beam to allow dynamics of the embedded particles to occur. Once the laser beam is switched off, the sample revitrifies within just a few microseconds, trapping the particles in their transient configurations, which can subsequently be imaged to obtain a snap shot of the dynamics at this point in time. While we have previousl

Ionization dynamics of resonantly excited helium nanodroplets have been studied by intense XUV light. By doping the nanodroplets with atoms that either attach to the surface or submerge into the center of the droplet, one can study the dynamics of excitati ...

The solvation of Ba+ ions created by the photoionization of barium atoms located on the surface of helium nanodroplets has been investigated. The excitation spectra corresponding to the 6p 2P1/2

A type of infrared imaging camera is demonstrated that uses gas-phase Rydberg atoms as photocathodes. The camera operates throughout the infrared part of the electromagnetic spectrum: l51 – 100 mm. The first results are presented and the potential of the camera as an ultrafast detector and a wavelength selective detector is discussed.

The dynamics following the photoexcitation of Ag atoms in 4He nanodroplets via the 5p 2P1=2 ← 5s2S1=2 and 5p 2P3=2 ← 5s2S1=2 transitions has been investigated in a joint experimental and theoretical effort. It has been experimentally found that upon excita ...

A 2 + 1 double-resonance laser-induced fluorescence technique is described in which the high power of a pulsed laser is combined with the narrow bandwidth of a single-mode cw ring dye laser. The combination of these laser systems allows the study of highly excited states with MHz resolution. This double-resonance technique has been applied to the study of the B-1 Sigma(+)(upsilon' = 0)

The photodissociation of (fluorinated) alkyl iodides in helium nanodroplets at a wavelength of 266 nm has been investigated by means of ion imaging techniques. It is found that a significant fraction of the created fragments escapes from the helium droplet ...

A novel approach to time-resolved cryo-electron microscopy (cryo-EM) has recently been introduced that involves melting a cryo sample with a laser beam to allow protein dynamics to briefly occur in the liquid, before trapping the particles in their transient configurations by rapidly revitrifying the sample. With a time resolution of just a few microseconds, this approach is notably fast enough to study the domain motions that are typically associated with the activity of proteins but which have previously

A method for reducing a preferred orientation of particles in a cryo-sample includes receiving the cryo-sample in a vacuum chamber, depositing amorphous ice onto the cryo-sample while the cryo-sample is in the vacuum chamber, delivering an energy pulse to the cryo-sample in the vacuum chamber to temporarily melt the amorphous ice on the cryo-sample to liquid water to promote movement of the particles in the cryo-sample to a changed orientation different from the preferred orientation, and allowing the liqui

Observing proteins as they perform their tasks has largely remained elusive, which has left our understanding of protein function fundamentally incom- plete. To enable such observations, we have recently proposed a technique that improves the time resoluti ...

The solvation dynamics of non-thermal species in liquid helium has been investigated by photolyzing alkyl iodide molecules, CH3I, C2H5I and CF3I, embedded in helium nanodroplets. The iodine and CH3 fragments are found to leave the droplets solvated by a fi ...

Evidence is presented of an unusual Rydberg system consisting of a helium nanodroplet containing a positively charged sodium ion and an orbiting electron. Rydberg states of this system with principal quantum number n

The excited state dynamics of silver atoms embedded in helium nanodroplets have been investigated by a variety of spectroscopic techniques. The experiments reveal that 5p 2P1/2 ← 5s 2S1/2 excitation of embedded silver atoms results almost exclusively in th ...

The large number of interactions in nanoscale systems leads to the emergence of complex behavior. Understanding such complexity requires atomic-resolution observations with a time resolution that is high enough to match the characteristic timescale of the ...

The photoionization dynamics of aniline doped helium droplets has been investigated by photoelectron spectroscopy. The photoelectron spectra resemble closely that of gas phase aniline, except for a dropletsize- dependent shift. This shift is caused by lowe ...

The vitrification of aqueous solutions through rapid cooling is a remarkable achievement that launched the field of cryo-electron microscopy (cryo-EM) and has enabled the cryopreservation of biological specimens. For judging the feasibility of a vitrificat ...

Water vitrifies if cooled at rates above 3 × 105 K/s. In contrast, when the resulting amorphous ice is flash heated, crystallization occurs even at a more than 10 times higher heating rate, as we have recently shown. This may present an issue for microseco ...

Marcel Drabbels

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Steric asymmetry in state-resolved NO-Ar collisions

Rapid melting and revitrification as an approach to microsecond time-resolved cryo-electron microscopy

Nucleation of quantized vortex rings in 4He nanodroplets

Microsecond melting and revitrification of cryo samples with a correlative light-electron microscopy approach

Migration of surface excitations in highly-excited nanosystems probed by intense resonant XUV radiation

Barium Ions and Helium Nanodroplets: Solvation and Desolvation

Infrared imaging camera based on a Rydberg atom photodetector

Translational dynamics of photoexcited atoms in 4He nanodroplets: the case of silver

High resolution pulsed-cw double-resonance spectroscopy on the B-1 Sigma(+)(v'=0)

Photodissociation of Alkyl Iodides in Helium Nanodroplets I: Kinetic Energy Transfer

Microsecond melting and revitrification of cryo samples: protein structure and beam-induced motion

Methods to overcome preferred orientation in cryo-samples for single particle analysis

Fast viral dynamics revealed by microsecond time-resolved cryo-EM

Photodissociation of Alkyl Iodides in Helium Nanodroplets II: Solvation Dynamics

Unusual Rydberg System Consisting of a Positively Charged Helium Nanodroplet with an Orbiting Electron

Excited State Dynamics of Ag Atoms in Helium Nanodroplets

Visualizing Nanoscale Dynamics with Time-resolved Electron Microscopy

Photoelectron Spectroscopy of Doped Helium Droplets

Direct measurement of the critical cooling rate for the vitrification of water

Shaped Laser Pulses for Microsecond Time-Resolved Cryo-EM: Outrunning Crystallization during Flash Melting