The picture shows partially the interior of a spectrometer where laser light is guided through a system of mirrors and filters to a carbon nanotube sample underneath a microscope, so that every other light source is cut off and the response of the carbon nanotubes to this very specific wavelength frequency can be recorded with high accuracy.

Band gaps 


Carbyne has optical properties that depend on the length of the carbon chains. The numbers above the curves stand for the respective vibrational frequency, correlated to the length of the carbon chains as these are bombarded with laser lightNot only do  longer chains exhibit a lower frequency, we also found that the longest chains require a lower laser energy.



The fluorescence intensity of carbon nanotubes can be improved, on the left (red and green) by filling with carbyne, on the right (black) with a molecule called ferrocene. As these molecules have different sizes, differently thick nanotubes are affected differently by the interaction between host and molecule.

Chain growth (movie) 


The movie shows a simulation of the growth of carbon chains within a carbon nanotube, which is performed by a high temperature treatment. By applying adequate temperatures, smaller chains start moving along the nanotube axis to eventually coalesce with other small chains to a larger chain.

Freezing ice


The water is cooled below its freezing point, water molecules arrange in an open lattice structure, forming an ice nucleus (yellow sticks). This picture is taken from a computer simulation of the freezing process.

Freezing gold

nanocluster (movie)


Video of freezing gold nanocluster. This video was made with data obtained from a molecular dynamics simulation in which the motion of the system is followed atom by atom.

Cavitation (damage)


Propeller damaged by the effects of cavitation. When the pressure in water drops below the vapor pressure, small vapor bubbles can form, a process known as cavitation, which damages objects immersed in the fluid.

Cavitation (simulation)


Formation of a bubble in water under tension. Water is depicted in red (oxygen) and white (hydrogen) and the yellow spheres show the largest bubble in the system, which grows until abruptly transitioning to vapor.


Polymer network


The picture shows a network made from differently colored polymers (spaghetti) that is held together by cross-links, made of three contacts. The cross-links are depicted by black balls and connecting bars. An important question to answer is how this network deforms, when one changes the size of the simulation box.

The model


The picture shows a schematic of cross-linking a single chain with a metal-ion. The ion cross-links three parts of one or of different polymers. The number of cross-links changes the mechanical behavior of the chain. Where the number of cross-links is large, the deformation is small and where the number of cross-links is low, the deformation is high.



Simulation of the force needed to pull different kinds of cross-linkes. The figure shows two polymers that have the same number of cross-links, but where the cross-links connects three parts of a polymer (black), or form solely between two partners (grey). The different mechanical behavior between the two different types is clear. 

Trajectory (movie)


It shows the deformation of a polymer with exactly one cross-link that connects three parts of the polymer. This cross-link consists of three bonds. During deformation the bond connecting the two most distant parts of the polymer fails and soon a single remaining bond between two parts of the polymers forms.

Breaking graphene


Defects, rather than the perfect lattice, determine the properties of any material. For example, materials always start to break  at defects. Here is a computer simulation of a braking 2D layer of graphene.

Random walk


Image sequence showing a „hole“ in the graphene sample (two atoms are missing). The defect does not stay in one spot, but instead moves around during observation under the electron microscope. The defect performs a random walk driven by the irradiation.


under irradiation


Ordered structures can form under irradiation. In the video below these lines we can see how, through irradiation, a cluster of Si atoms (Silicon) forms.




Fullerenes (the soccer-ball shaped molecules) were embedded between two graphene sheets and studied by atomic-resolution STEM. This way we could observe the diffusion and rotation of the molecules. Due to the motion of the fullerenes at the edge, they are only partially visible.