Related papers: Photoabsorption in Sodium Clusters: First Principl…
We have performed systematic large-scale all-electron correlated calculations on boron clusters B$_{n}$(n=2--5), to study their linear optical absorption spectra. Several possible isomers of each cluster were considered, and their…
Absorption spectra of closed-shell Na_2, Na_3+, Na_4, Na_5+, Na_6, Na_7+, and Na_8 clusters are calculated using a recently implemented conserving linear response method. In the framework of a quasiparticle approach, we determine…
In this paper, we report large-scale configuration interaction (CI) calculations of linear optical absorption spectra of various isomers of magnesium clusters Mg$_{n}$ (n=2--5), corresponding to valence transitions. Geometry optimization of…
We report the linear optical absorption spectra of aluminum clusters Al$_{n}$ (n=2--5) involving valence transitions, computed using the large-scale all-electron configuration interaction (CI) methodology. Several low-lying isomers of each…
The linear optical absorption spectra in neutral boron cluster B$_{6}$ and cationic B$_{6}^{+}$ are calculated using a first principles correlated electron approach. The geometries of several low-lying isomers of these clusters were…
We have performed systematic large-scale all-electron correlated calculations on boron Bn, aluminum Aln and magnesium Mgn clusters (n=2--5), to study their linear optical absorption spectra. Several possible isomers of each cluster were…
We present ground-state configurations and photoabsorption spectra of Na-7+, Na-27+ and Na-41+. Both the ionic structure and the photoabsorption spectra of medium-size sodium clusters beyond Na-20 have been calculated self-consistently with…
The choice of Gaussian basis functions for computing the ground-state properties of molecules, and clusters, employing wave-function-based electron-correlated approaches, is a well-studied subject. However, the same cannot be said when it…
We have performed first principles electron-correlated calculations employing large basis sets to optimize the geometries, and to compute linear optical absorption spectra of various low-lying conformers of silicon hydrides:…
Photoabsorption cross sections of small sodium cluster cations (Na$_n^+$, n=3,5,7 and 9) were calculated at various temperatures with the time-dependent local-density-approximation (TDLDA) in conjunction with ab initio molecular dynamics…
We predict the strong enhancement in the photoabsorption of small Mg clusters in the region of 4-5 eV due to the resonant excitation of the plasmon oscillations of cluster electrons. The photoabsorption spectra for neutral Mg clusters…
We determined the ionic and electronic structure of sodium clusters with even electron numbers and 2 to 59 atoms in axially averaged and three-dimensional density functional calculations. A local, phenomenological pseudopotential that…
The question whether the linear absorption spectra of metal clusters can be interpreted as density oscillations (collective ``plasmons'') or can only be understood as transitions between distinct molecular states is still a matter of debate…
The line shape of the plasma resonance in both neutral and charged small sodium clusters is calculated. The overall properties of the multipeak structure observed in the photoabsorption cross section of spherical Na_8 and Na_20 neutral…
Embedded Si and Ge nanocrystals (NCs) in wide band-gap matrices are studied theoretically using an atomistic pseudopotential approach. From small clusters to large NCs containing on the order of several thousand atoms are considered.…
We present a method for computing optical absorption spectra by means of a Bethe-Salpeter equation approach, which is based on a conserving linear response calculation for electron-hole coherences in the presence of an external…
We revisit the photoabsorption from the ground state of Na, ending below and above the ionization threshold, with special emphasis on the shape of the photoionization cross section around the Cooper minimum. The present treatment, using a…
Some properties of small and medium sodium clusters are described within the RPA approach using a projected spherical single particle basis. The oscillator strengths calculated with a Schiff-like dipole transition operator and folded with…
Novel equations for the electric dipole polarizability $\alpha_{_{E1}}$ of low-lying excited states in atomic nuclei -- and the related $(-2)$ moment of the total photo-absorption cross section, $\sigma_{_{-2}}$ -- are inferred in terms of…
The present work reports new total photoabsorption cross sections for the $N=Z$ nuclei in the $sd$-shell $^{20}$Ne, $^{24}$Mg, $^{28}$Si, $^{32}$S, $^{36}$Ar, and for $^{26}$Mg. The results are compared to predictions of a data-driven…