The lowest energy structures of ${\mathrm{Au}}_{n}$ ( $n\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}38,55,75$) nanoclusters are obtained by unconstrained dynamical and genetic-symbiotic optimization methods, using a Gupta $n$-body potential. A set amorphous structures, nearly degenerate in energy, found as the most stable configurations. Some crystalline or quasicrystalline isomers also minima cluster potential surface with similar energy. First principles calculations density...

The geometries and binding energies of the most stable isomers nickel, silver, gold nanoclusters size 6, 7, 12, 13, 14, 19, 38, 55, 75 atoms, predicted with an n-body Gupta potential, are presented. An exhaustive search for low-energy minima on potential energy surface was carried out using evolutive (genetic-symbiotic) algorithm. Our results confirm existence disordered global clusters 55 atoms in size, 75-atom cluster. Disordered structures also nickel silver but they not among these...

Chiral structures have been found as the lowest-energy isomers of bare (Au$_{28}$ and Au$_{55}) thiol-passivated (Au$_{28}(SCH$_{3})$_{16}$ Au$_{38}(SCH_{3})_{24}) gold nanoclusters. The degree chirality existing in chiral clusters was calculated using Hausdorff measure. We that index is higher passivated decreases with cluster size. These results are consistent observed chiroptical activity recently reported for glutahione-passivated nanoclusters, provide theoretical support existence these...

Knowledge of the structure clusters is essential to predict many their physical and chemical properties. Using a many-body semiempirical Gupta potential (to perform global minimizations), first-principles density functional calculations confirm energy ordering local minima), we have recently found [Phys. Rev. Lett. 81, 1600 (1998)] that there are intermediate-size disordered gold nanoclusters with near or below lowest-energy ordered structure. This especially surprising because studied...

A Comment on the Letter by H. Hakkinen, R. N. Barnett, and U. Landman, Phys. Rev. Lett. 82, 3264 (1999).Received 30 March 2000DOI:https://doi.org/10.1103/PhysRevLett.85.5250©2000 American Physical Society

Abstract. Understanding the thermodynamic function of life may shed light on its origin. Life, as are all irreversible processes, is contingent entropy production. Entropy production a measure rate tendency Nature to explore available microstates. The most important process generating in biosphere and, thus, facilitating this exploration, absorption and transformation sunlight into heat. Here we hypothesize that began, persists today, catalyst for dissipation surface Archean seas. resulting...

Abstract. The driving force behind the origin and evolution of life has been thermodynamic imperative increasing entropy production biosphere through global solar photon dissipation rate. In upper atmosphere today, oxygen ozone derived from processes are performing short-wavelength UV-C UV-B dissipation. On Earth's surface, water organic pigments in facilitate near-UV visible first probably formed, absorbed, dissipated at those photochemically active wavelengths that could have reached...

Abstract Experiments were carried out using a loop in three fields (gassy-oil, oily-gas, and oil-transmission pipes) under 17 operating conditions, six inhibitors (three continuous ...

Some fundamental molecules of life are suggested to have been formed, proliferated, and evolved through photochemical microscopic dissipative structuring autocatalytic proliferation under the UV-C/UV-B solar environment prevalent at Earth's surface throughout Archean. Evidence is given in numerous salient characteristics these, including their strong absorption this spectral region rapid non-radiative excited state decay inherent conical intersections. The examples purines single strand DNA...

There is little doubt that life’s origin followed from the known physical and chemical laws of Nature. The most general scientific framework incorporating Nature applicable to processes good approximation, thermodynamics its extensions treat out-of-equilibrium phenomena. event life should therefore also be amenable such an analysis. In this review paper, I describe non-equilibrium thermodynamic foundations for non-expert perspective “Thermodynamic Dissipation Theory Origin Life” which...

I describe the non-equilibrium thermodynamics and photochemical mechanisms which may have been involved in dissipative structuring, proliferation evolution of fundamental molecules at origin life from simpler more common precursor under impressed UVC photon flux Archean. Dissipative structuring is evidenced by their strong broad wavelength absorption bands rapid radiationless dexcitation this region. Proliferation arises auto- cross-catalytic nature intermediate products. Evolution towards...

There is little doubt that life's origin followed from the known physical and chemical laws of Nature. The most general scientific framework incorporating Nature applicable to processes good approximation, thermodynamics its extensions treat out-of-equilibrium phenomena. event life should therefore also be amenable such an analysis. In this paper, I describe non-equilibrium thermodynamic foundations for non-expert. This ``Thermodynamic Dissipation Theory Origin Life'' founded on Classical...

Heat capacities of ${\mathrm{Na}}_{N},$ $N=13,$ 20, 55, 135, 142, and 147, clusters have been investigated using a many-body Gupta potential microcanonical molecular-dynamics simulations. Negative heat around the cluster meltinglike transition obtained for $N=135,$ but smaller $(N=13,$ 55) do not show this peculiarity. By performing survey potential-energy landscape (PEL), it is found that width distribution function kinetic energy spread minima (isomers) are useful features to determine...

A proton-proton bremsstrahlung experiment has been carried out at TRIUMF using a 280-MeV polarized proton beam impinging on liquid-hydrogen target. All three outgoing particles were detected: the higher-energy in magnetic spectrometer, lower-energy with plastic scintillators, and photon lead-glass Cherenkov detectors. The shows first unambiguous evidence for off-shell effects free nucleon-nucleon interaction, that analyzing powers disagree strongly predictions of soft-photon approximation...

A model is proposed to describe the production of light induced by energetic ions in scintillator materials, based on distribution energy deposited secondary electrons produced along ion's track. The initial determined using an impulse approximation which their motion constrained radial direction, perpendicular residual coordinate obtained from expression for specific loss Lindhard's potential theory. Contributions backscattered deposition are included calculation. Local carriers assumed be...

Trapped ion electron diffraction measurements on silver cluster cations, $\mathrm{Ag}_{n}{}^{+}$ for sizes $n=36--46,55$ at $\ensuremath{\sim}120\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ describe an evolution in structural symmetry with increasing size. Diffraction patterns characterize fivefold smaller which evolves to icosahedral $n=55$. Low energy isomer structures were identified by statistical search methods and optimized density-functional calculations. Comparison of data these...

Abstract. Darwinian theory depicts life as being overwhelmingly consumed by a fight for survival in hostile environment. However, from thermodynamic perspective, is dynamic, out of equilibrium process, stabilizing and coevolving concert with its abiotic The living components the biosphere on Earth's surface greatest biomass, plants cyanobacteria, are involved transpiration vast amount water. Transpiration part global water cycle, it this cycle that distinguishes Earth apparently life-barren...

Non-equilibrium thermodynamics is a relevant framework from within which to address formidable difficulties encountered in explaining the origin of life; molecular synthesis and complexation, enzyme-less proliferation, evolution (including acquisition homochirality information). From this we have proposed that life was dissipative structuring organic pigments became fundamental molecules (e.g. RNA DNA) proliferated through autocatalytic photochemical reactions under thermodynamic imperative...

Through a modern derivation of Planck's formula for the entropy an arbitrary beam photons, we derive general expression production due to irreversible process absorption incident photon spectrum in material and its dissipation into infrared-shifted grey-body emitted spectrum, with rest being reflected or transmitted. Employing framework Classical Irreversible Thermodynamic theory, define generalized thermodynamic flow as photons from force is, then, divided by flow, which is per unit at...

We have proposed that the abiogenesis of life around beginning Archean may been an example "spontaneous" microscopic dissipative structuring UV-C pigments under prevailing surface ultraviolet solar spectrum. The thermodynamic function these (the "fundamental molecules life"), as for visible today, was to dissipate incident light into heat. previously described non-equilibrium thermodynamics and photochemical mechanisms which involved in purines adenine hypoxanthine from common precursor...

Abstract. Understanding the thermodynamic function of life may shed light on its origin. Life, as are all irreversible processes, is contingent entropy production. Entropy production a measure rate tendency Nature to explore available microstates. The most important process generating in biosphere and, thus, facilitating this exploration, absorption and transformation sunlight into heat. Here we hypothesize that began, persists today, catalyst for dissipation surface shallow seas. resulting...

Since a racemic mixture of chiral nucleotides frustrates the enzymeless extension RNA and DNA, origin homochirality must be intimately connected with life. Homochirality theories have elected to presume abiotic mechanisms for prebiotic enantiomer enrichment post amplification, but none, so far, has been generally accepted. Here I present novel hypothesis procurement from an asymmetry in right- over left-circularly polarized photon-induced denaturing DNA at Archean ocean surface as...