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Gold and gold-based clusters are still receiving special attention owing to their diverse applicability. Density functional theory (DFT) calculations were employed to investigate the structures, the lone-pair affinity of some small Aun clusters (n = 16, 17, and the effects of chromium dopant on their properties. Regarding Au16, the boat-like Cs conformation and the hollow Td form are found to be energetically quasi-degenerate and strongly competing as the ground state. In terms of Au17, a star-like cage is computed to be more stable than the putative global minimum reported in preceding studies. Given Au16Cr isomer, a novel structure for the lowest energy is proposed. Binding energies of these species with CO, NH3, and PH3 ligands are also provided as an in-depth reference to the literature. Present results altogether encourage further theoretical implementations, e.g., CCSD(T) and experimental probes, e.g., the infrared, to validate the findings, thus harnessing the potentiality of the complexes. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations were carried out to explore the geometric, spectroscopic, and electronic properties of three magic silver clusters Agn (n = 8, 18, and 20) in detail. The computed results show that the global minima of these clusters are compact, near-spherical structures, while other low-lying isomers exhibit oblate or prolate shapes. Vertical ionization energies for the low-lying isomers were also computed and assigned with respect to available experimental values. Although several isomers were predicted to have similar energies, their electronic and vibrational signatures were quite distinctive, meaning that they could be used as fingerprint signals to distinguish between isomers. In addition, the electronic structures of these systems were explored using the phenomenological shell model. Calculations for the coinage metal clusters M20 (M = Cu, Ag, Au) indicated that the structures and properties of the Ag cluster are similar to those of the Cu cluster in that both Cu20 and Ag20 prefer a compact structure whereas Au20 prefers to adopt a tetrahedral form.Shell Orbitals of Ag8 Cluster [ABSTRACT FROM AUTHOR]

Gold and gold-based clusters are still receiving special attention owing to their diverse applicability. Density functional theory (DFT) calculations were employed to investigate the structures, the lone-pair affinity of some small Au n clusters (n = 16, 17, and the effects of chromium dopant on their properties. Regarding Au 16 , the boat-like C s conformation and the hollow T d form are found to be energetically quasi-degenerate and strongly competing as the ground state. In terms of Au 17 , a star-like cage is computed to be more stable than the putative global minimum reported in preceding studies. Given Au 16 Cr isomer, a novel structure for the lowest energy is proposed. Binding energies of these species with CO, NH 3 , and PH 3 ligands are also provided as an in-depth reference to the literature. Present results altogether encourage further theoretical implementations, e.g., CCSD(T) and experimental probes, e.g., the infrared, to validate the findings, thus harnessing the potentiality of the complexes., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Density functional theory (DFT) calculations are employed to examine the adsorption behaviors of cysteine on the gold surface using Au 6 and Au 8 species as model reactants. Computed results show that cysteine molecules prefer to bind with gold clusters via the S-atom of the thiol group in vacuum and thiolate group in water. The gas-phase adsorption energies are around 20.2 kcal/mol for Au 6 and 24.4 kcal/mol for Au 8 . In water environment, such values are slightly reduced for Au 6 (19.6 kcal/mol), but increased a little more for Au 8 (25.6 kcal/mol). As a result, if a visible light with a frequency of ν ≈ 6 × 10 14  Hz (500 nm) is applied, the time for the recovery of Au 6 and Au 8 from the most stable complexes will be about 0.38 and 9.3 × 10 3  s, respectively, at 298 K in water. The Au 6 is in addition found to benefit from a larger change of energy gap that could be converted to an electrical signal for detection of cysteine.

Density functional theory (DFT) calculations were carried out to explore the geometric, spectroscopic, and electronic properties of three magic silver clusters Ag n (n = 8, 18, and 20) in detail. The computed results show that the global minima of these clusters are compact, near-spherical structures, while other low-lying isomers exhibit oblate or prolate shapes. Vertical ionization energies for the low-lying isomers were also computed and assigned with respect to available experimental values. Although several isomers were predicted to have similar energies, their electronic and vibrational signatures were quite distinctive, meaning that they could be used as fingerprint signals to distinguish between isomers. In addition, the electronic structures of these systems were explored using the phenomenological shell model. Calculations for the coinage metal clusters M 20 (M = Cu, Ag, Au) indicated that the structures and properties of the Ag cluster are similar to those of the Cu cluster in that both Cu 20 and Ag 20 prefer a compact structure whereas Au 20 prefers to adopt a tetrahedral form. Graphical abstract Shell Orbitals of Ag 8 Cluster.