Atomic and Molecular Clusters
Using synchrotron radiation we simultaneously ionize and excite one helium atom of a helium dimer (He_2) in a shakeup process. The populated states of the dimer ion (i.e. He^[*+](n = 2; 3)-He) are found to deexcite via interatomic coulombic…
Optimal control techniques combined with femtosecond laser pulse shaping are applied to steer and enhance the strong-field induced emission of highly charged atomic ions from silver clusters embedded in helium nanodroplets. With light…
Laser excitation of nanometer-sized atomic and molecular clusters offers various opportunities to explore and control ultrafast many-particle dynamics. Whereas weak laser fields allow the analysis of photoionization, excited-state…
Intense 3-cycle pulses (10 fs) of 800 nm laser light are utilized to measure energy distributions of ions emitted following Coulomb explosion of Ar$_n$ clusters ($n$=400-900) upon their irradiation by peak intensitis of 5$\times$10$^{14}$ W…
The structure of small mixed helium clusters doped with one calcium atom has been determined within the diffusion Monte Carlo framework. The results show that the calcium atom sits at the $^4$He-$^3$He interface. This is in agreement with…
The total photodetachment cross section of a linear triatomic anion is derived for arbitrary laser polarization direction. The cross section is shown to be strongly oscillatory when the laser polarization direction is parallel to the axis…
We show that our procedure of constructing excited-state energy functionals by splitting k-space, employed so far to obtain exchange energies of excited-states, is quite general. We do so by applying the same method to construct modified…
In this work, a shell model for metal clusters up to 220 valence electrons is used to obtain the fractional occupation probabilities of the electronic orbitals. Then, the calculation of a statistical measure of complexity and the…
Alkali atoms do not stably embed in liquid helium-4 because the interatomic attractive potential is unable to overcome the short-range Pauli repulsion of the s electrons and the surface tension cost of the surrounding bubble. Similarly,…
In this work, we report electronic structure calculations aimed at computing the linear optical absorption spectrum, and static dipole polarizablity of a newly proposed boron-based planar aromatic compound borozene (B_12H_6$. For the…
In this paper, we present a theoretical investigation of photoabsorption spectrum of the newly synthesized hydrogenated cluster of aluminium, Al4H6. The calculations are performed within the wave-function-based semi-empirical method…
We present recent theoretical investigations on the dynamics of metal clusters in contact with an environment, deposited of embedded. This concerns soft deposition as well as irradiation of the deposited/embedded clusters by intense laser…
Boron clusters have been widely studied theoretically for their geometrical properties and electronic structure using a variety of methodologies. An important cluster of boron is the B$_{12}$ cluster whose two main isomers have distinct…
Electron affinity, electronegativity and electrophilicity of several neutral atoms and their positive and negative ions are calculated at various levels of theory using different basis sets in the gas phase as well as in the presence of…
Stability, reactivity and aromaticity of clusters of various noble gas atoms trapped in aromatic H3+ and Li3+ rings are studied at the B3LYP/6-311+G(d) and MP2/6-311+G(d) levels of theory. Electrophilicity, gain in energy and nucleus…
Relaxation processes following inner-valence ionization of a system can be modified dramatically by embedding this system in a suitable environment. Surprisingly, such an environment can be even composed of helium atoms, the most inert…
We outline a method to slow paramagnetic atoms or molecules using pulsed magnetic fields. We also discuss the possibility of producing trapped particles by adiabatic deceleration of a magnetic trap. We present numerical simulation results…
The static response properties and the structural stability of silver clusters in the size range $1\le n \le 23$ have been studied using a linear combination of atomic Gaussian-type orbitals within the density functional theory in the…
With a semiclassical quasi-static model we achieve an insight into the complex dynamics of two correlated electrons under the combined influence of a two-center Coulomb potential and an intense laser field. The model calculation is able to…
Clusters of the electronically excited condensed matter Rydberg Matter (RM) are planar and six-fold symmetric with magic numbers N = 7, 19, 37, 61 and 91. The bond distances in the clusters are known with a precision of +- 5% both from…