Squeezing a helium nanodroplet with a Rydberg electron.

J Phys Chem A

INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica G. Galilei, Università di Padova, via Marzolo 8, I-35131 Padova, Italy.

Published: December 2007

We have investigated, by means of density functional theory, the structure of a "scolium", that is, an electron circulating around a positively charged 4He nanodroplet, temporarily prevented from neutralization by the helium-electron repulsion. The positive ion core resides in the center of the nanodroplet where, as a consequence of electrostriction, a strong increase in the helium density with respect to its bulk value occurs. The electron enveloping the 4He cluster exerts an additional electrostatic pressure which further increases the local 4He density around the ion core. We argue that under such pressure, sufficiently small 4He nanodroplets may turn solid. The stability of a scolium with respect to electron-ion recombination is investigated.

Download full-text PDF

Source
http://dx.doi.org/10.1021/jp076069bDOI Listing

Publication Analysis

Top Keywords

ion core
8
squeezing helium
4
helium nanodroplet
4
nanodroplet rydberg
4
rydberg electron
4
electron investigated
4
investigated density
4
density functional
4
functional theory
4
theory structure
4

Similar Publications

Flaky sputtered silicon MWCNTs core-shell structure as a freestanding binder-free electrode for lithium-ion battery.

Sci Rep

January 2025

Nano-fabricated Energy Devices Lab, School of Electrical and Computer Eng., University of Tehran, 14395-515, Tehran, Iran.

Core-shell silicon/multiwall carbon nanotubes are one of the most promising anode candidates for further improvement of lithium-ion batteries. Sufficient accommodation for massive volume expansion of silicon during the lithiation process and preventing pulverization and delamination with easy fabrication processes are still critical issues for practical applications. In this study, core-shell silicon/MWCNTs anode materials were synthesized using a facile and controllable PECVD technique to realize aligned MWCNTs followed by a silicon sputtering step.

View Article and Find Full Text PDF

Coordination-driven metallo-supramolecular polymers hold significant potential as highly efficient catalysts for photocatalytic CO reduction, owing to the covalent integration of the light harvesting unit, catalytic center and intrinsic hierarchical nanostructures. In this study, we present the synthesis, characterization, and gelation behaviour of a novel low molecular weight gelator (LMWG) integrating a benzo[1,2-:4,5-']dithiophene core with terpyridine (TPY) units alkyl amide chains (TPY-BDT). The two TPY ends of the TPY-BDT unit efficiently chelate with metal ions, enabling the formation of a metallo-supramolecular polymer that brings together the catalytic center and a photosensitizer in close proximity, maximizing catalytic efficiency for CO reduction.

View Article and Find Full Text PDF

Carbon capture and storage (CCS) and CO-based geothermal energy are promising technologies for reducing CO emissions and mitigating climate change. Safe implementation of these technologies requires an understanding of how CO interacts with fluids and rocks at depth, particularly under elevated pressure and temperature. While CO-bearing aqueous solutions in geological reservoirs have been extensively studied, the chemical behavior of water-bearing supercritical CO remains largely overlooked by academics and practitioners alike.

View Article and Find Full Text PDF

Retention mechanism in slalom chromatography: Perspectives on the characterization of large DNA and RNA biopolymers in cell and gene therapy.

J Chromatogr A

January 2025

Waters Corporation, Instrument/Core Research/Fundamental, Milford, MA, 01757, USA. Electronic address:

Significant progress has been made in the last two decades in producing small (<2μm), high-purity, and low-adsorption particles, columns and system hardware, for ultra-high pressure liquid chromatography (UHPLC). Simultaneously, the recent rapid expansion of cell and gene therapies for treating diseases necessitates novel analytical technologies for analyzing large (>2 kbp) plasmid double-stranded (ds) DNA (which encodes for the in vitro transcription (IVT) of single-stranded (ss) mRNA therapeutics) and dsRNAs (related to IVT production impurities) biopolymers. In this context, slalom chromatography (SC), a retention mode co-discovered in 1988, is being revitalized using the most advanced column technologies for improved determination of the critical quality attributes (CQAs) of such new therapeutics.

View Article and Find Full Text PDF

Investigate the impact of antimicrobial photodynamic therapy (aPDT) using different photosensitizers (PSs) such as indocyanine green (IG), curcumin (CC), and methylene blue (MB), with or without intracanal application of calcium hydroxide (CH), on the push-out bond strength of glass-fiber posts (GFPs) to intraradicular dentin, the chemical composition of the root substrate, and the sealing of the adhesive interface across different thirds of intraradicular dentin. A total of 112 bovine teeth underwent biomechanical preparation and were divided into eight experimental groups (n = 14 each): Negative control with deionized water; positive control with deionized water + CH; IG group with indocyanine green and infrared laser; IG + CH group; CC group with curcumin and blue LED; CC + CH group; MB group with methylene blue and red laser; and MB + CH group. The push-out bond strength was measured using a universal testing machine (n = 8), and scanning electron microscopy characterized the fracture patterns.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!