Valence photoionization of small alkaline earth atoms endohedrally confined in C60

• Published in: The European physical journal. D, Atomic, molecular, and optical physics Atomic, molecular, and optical physics, 2012, Vol.66 (7), Article 189
• Main Authors: Javani, M. H., McCreary, M. R., Patel, A. B., Madjet, M. E., Chakraborty, H. S., Manson, S. T.
• Format: Article
• Language: English
• Subjects: Applications of Nonlinear Dynamics and Chaos Theory; Atomic; Atomic and molecular clusters; Atomic and molecular physics; Atomic properties and interactions with photons; Calculations and mathematical techniques in atomic and molecular physics (excluding electron correlation calculations); Density-functional theory; Electronic structure of atoms, molecules and their ions: theory; Exact sciences and technology; Molecular; Optical and Plasma Physics; Optical properties of clusters; Photoionization of atoms and ions; Photon interactions with atoms; Physical Chemistry; Physics; Physics and Astronomy; Quantum Information Technology; Quantum Physics; Regular Article; Spectroscopy/Spectrometry; Spintronics; Studies of special atoms, molecules and their ions; clusters; Topical issue: Atomic Cluster Collisions
• ISSN: 1434-6060; 1434-6079
• DOI: 10.1140/epjd/e2012-30081-9

A theoretical study of photoionization from the outermost orbitals of Be, Mg and Ca atoms endohedrally confined in C 60 is reported. The fullerene ion core, comprised of sixty C 4+ , is smudged into a continuous jellium charge distribution, while the delocalized cloud of carbon valence electrons plus the encaged atom are treated in the time-dependent local density approximation (TDLDA). Systematic evolution of the mixing of outer atomic level with states of the C 60 valence band is found along the sequence. This is found to influence the plasmonic enhancement of atomic photoionization at low energies and the geometry-revealing confinement oscillations at high energies in significantly different ways: (a) the extent of enhancement is mainly determined by the strength of atomic ionization, giving the strongest enhancement for Be even though Ca suffers the largest mixing. But (b) strongest collateral oscillations are uncovered for Ca, since, relative to Be and Mg, the mixing causes the highest photoelectron production at confining boundaries of Ca. The study paints the first comparative picture of the atomic valence photospectra for alkaline earth metallofullerenes in a dynamical many-electron framework.