Electronic excitations of stable fullerene-like GaP clusters

2004 ◽  
Vol 854 ◽  
Author(s):  
Giuliano Malloci ◽  
Giancarlo Cappellini ◽  
Giacomo Mulas ◽  
Guido Satta

ABSTRACTWe present quasi-particle (QP) corrections to the electronic energies for small GaP fullerenes, a new class of nanoscaled materials predicted to be stable and to show spontaneous formation. Using Time-Dependent Density Functional Theory we also computed the optical absorption spectra. The comparison between single-particle and optical absorption spectra yields strong excitonic effects with bonding energy up to 3.5 eV. The QP corrected HOMO-LUMO energy gaps confirm the high stability predicted for such molecules using ground-state computational schemes. The present results can be useful to identify the successful synthesis of these systems via optical absorption and QP spectra.

NANO ◽  
2016 ◽  
Vol 11 (08) ◽  
pp. 1650086 ◽  
Author(s):  
Mukerem H. Abib ◽  
Xudong Yao ◽  
Guopeng Li ◽  
Longfei Mi ◽  
Yajing Chang ◽  
...  

Geometrical structures of (ZnSe)n, [Formula: see text], ([Formula: see text] 1–4) and (MnxZn[Formula: see text]Se[Formula: see text], ([Formula: see text] clusters were calculated using density functional theory (DFT). Optical/absorption spectra, Raman spectra, HOMO–LUMO gap energy and binding energy of each cluster were calculated. The calculated results show the red shift of the optical/absorption spectra band caused by the manganese atoms doped in ZnSe clusters, and the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO–LUMO) gap energy value is decreased. Furthermore, we realized highly monodispersed manganese-doped zinc selenide quantum dots (Mn:ZnSe d-dots) experimentally by using a convenient route. The as-synthesized Mn:ZnSe d-dots were characterized by UV-Vis absorption, photoluminescence (PL), X-ray diffraction (XRD), TEM and HRTEM. The experimental results revealed that the as-prepared Mn:ZnSe d-dots with zinc-blende structure have an average size of about 3.9 nm.


2012 ◽  
Vol 26 (13) ◽  
pp. 1250089 ◽  
Author(s):  
X. H. HONG ◽  
F. WANG ◽  
C. H. DU ◽  
B. C. GOU

The optical absorption spectra have been calculated for two isomers of Na 4 based on a real-space, real-time implementation of time-dependent density functional theory (TDDFT). We find that our spectra of two Na 4 isomers are in very good agreement with experimental spectra in peak positions and peak intensities. Our results give a good explanation of the discrepancy between the two experimental spectra. Furthermore, we discuss the influence of different isomers on the optical absorption spectra.


RSC Advances ◽  
2016 ◽  
Vol 6 (76) ◽  
pp. 72537-72543
Author(s):  
Sandip Kumavat ◽  
Sudip Chakraborty ◽  
Amol B. Rahane ◽  
Mrinalini D. Deshpande ◽  
Rajeev Ahuja

The optical absorption spectra and static polarizabilities for the lowest energy configurations of Al2O3 and Gd doped (Al2O3)n clusters (n = 1–10) are investigated based on the time-dependent density functional theory (TDDFT) formalism.


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