Polycyclic aromatic hydrocarbons (PAHs) are a class of organic molecules based on two or more fused aromatic rings, with hexagonal rings as typical dominant constituents. They are found and formed in a wide variety of environments. In the case of extraterrestrial environments, PAHs are believed to be an important component in interstellar dust and gas and as such are responsible for infrared...
Quantum computers are predicted to achieve significant speed-ups for certain applications when compared to classical computers. In this talk, I give an overview of quantum computing in rare-earth-ion-doped crystals, including the results of recent theoretical investigations that show that quantum processor nodes constructed in these materials can be tailored to contain between a few tens and...
Ultrafast control of light-matter interactions is fundamental in view of new technological frontiers, for instance in light-driven information processing and nanoscale photo-chemistry. In this framework, we explore metal-dielectric nanocavities to achieve all-optical modulation of the light reflectance at a specific wavelength. Without the need of driving higher order effects, our system is...
The chemical composition of a star provides information about the environment in which it was born. This, in turn, makes it possible to study the formation and evolution of our Galaxy. Reliable abundance analysis of various elements in stellar spectra require an understanding of the atomic nature, in the form of accurate atomic transition data. By combining radiative lifetimes with relative...
The infrared spectrum of a molecular system is traditionally calculated from energy derivatives at its equilibrium geometry. Such methods are inherently limited to a single static point, and cannot describe anharmonic potential features such as the ergodic double-well. A more recent approach is to simulate classical vibration with Born-Oppenheimer molecular dynamics, freely exploring the...
Using synchrotron radiation and state of the art instruments we uncover more about the electronic structure of N$_2$. In this presentation we will look at new core-excited states in N$_2^+$ studied by X-ray absorption spectroscopy and how the vibrational wavefunction of N$_2$ can be imaged by resonant inelastic X-ray scattering.
The region in the water’s phase diagram called “no-man’s land” (160K - 232 K) [1,2] has incited vast research. It is within its depths that the origin of water’s anomalous properties is thought to hide behind a veil of crystallisation [3,4]. However, there are other open questions in this region regarding the early stages of crystallisation itself, particularly that of the structure of ice....
The interaction between ultraintense laser light (10^20 W/cm2) and nanotips can produce electron bunches with interesting properties, such as relativistic energy (1-10MeV), high charge (nC) and pulse duration expected in the attosecond regime. Experimental results about the angular distribution, charge and spectrum will be shown and explained using the vacuum laser acceleration mechanism.
There very first example a student learns in quantum mechanics is the square potential well. However, when working with atoms we use spherical coordinates and a spherical potential well would be a much closer analogy. After writing the Schrödinger equation in spherical coordinates, the centrifugal barrier ($\ell (\ell + 1) /r^{2}$) appears, which, when added to a square potential well in the...
It has been widely recognized in the scientific community that scarce elements such as ruthenium are not ideal for sustainable technology. During the past 10 years, progress has been made in exploring first-row transition metals as replacements for scarce metals in many solar cell and photocatalysis applications.[1] Iron analogues to well-performing ruthenium-complexes were early found to not...
Nitrosyl-containing iron complexes (FeNO) have attracted many studies focusing on the mechanisms of NO binding in heme and NO release by a photoactivated nitric oxide-releasing moiety complex. M-NO and M-CO bonds form by $\sigma$-donation to an unoccupied metal orbital and the bond is strengthened by $\pi$-back donation from a filled metal d-orbital to the unoccupied $\pi^*$ orbitals on the...