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The present authors would like to update some data reported in Fig. 5. The vertical axis label should be DEAFM–FM with VASP and FHI-AIMS, and there was a transcription error in some FHI-AIMS PBE values. In consequence, the corresponding values from Table S4 in the supplementary information should also be replaced. All results, discussions, and conclusions from the original article are unaffected by the present correction. The corrected Fig. 5 is presented below and the correct table has been modified in the supplementary information.
Scientists have created a powerful new way to control quantum systems, achieving the first-ever demonstration of quadsqueezing—an elusive fourth-order quantum effect。 By combining simple forces in a clever way, they made previously hidden quantum behaviors visible and usable, opening new frontiers for quantum technology
Physicists have taken a major step toward using AI not just to analyze data, but to uncover entirely new laws of nature。 By combining a specially designed neural network with precise 3D tracking of particles in a dusty plasma—a strange “fourth state of matter” found from space to wildfires—the team revealed hidden patterns in how particles interact
In a striking glimpse into extreme physics, scientists have captured the split-second chaos that unfolds when powerful laser flashes blast matter into a superheated plasma。 By combining two cutting-edge lasers, researchers were able to track how copper atoms lose and regain electrons in trillionths of a second, creating and dissolving highly charge
A team at King’s College London has created a powerful new aluminum compound capable of doing the work of expensive rare metals。 Its unique triangular structure gives it remarkable stability and reactivity, allowing it to drive chemical reactions in ways never seen before。 The discovery could lead to greener and far more affordable industrial proce
A group of undergraduate students pulled off something remarkable: they built their own dark matter detector and used it to probe one of physics’ biggest mysteries。 Working with limited resources but plenty of creativity, they designed a stripped-down experiment to hunt for axions — hypothetical particles that could make up dark matter
Quantum physics once shocked scientists by revealing that particles can behave like waves—and now, that strange behavior has been pushed even further。 For the first time, researchers have observed wave-like interference in positronium, an exotic “atom” made of an electron and its antimatter partner, a positron。 This breakthrough not only strengthen
A surprising breakthrough in physics could reshape the future of computing by tapping into a strange, previously untapped property of matter。 Scientists have shown that tiny atomic vibrations—called chiral phonons—can directly transfer motion to electrons, allowing them to carry information without magnets, batteries, or even electricity。 This open
A major new study finds that living in pesticide-heavy environments could raise cancer risk by up to 150%, even when the chemicals are considered “safe” on their own。 The research suggests these mixtures may silently damage cells years before cancer appears
Scientists have uncovered a surprising new layer of complexity in Cannabis, identifying dozens of previously unknown compounds—including the first-ever evidence of rare molecules called flavoalkaloids in its leaves。 These compounds, prized for their potential health benefits, were hidden among a rich mix of plant chemicals that vary dramatically ev
Curiosity has detected a surprising variety of organic molecules on Mars, including compounds tied to the chemistry of life。 Some of these molecules may be billions of years old, preserved in ancient clay-rich rocks that once held water。 One standout find resembles building blocks of DNA, raising exciting questions about Mars’ past
A major physics experiment has uncovered evidence for a strange new form of matter, where a fleeting particle gets trapped inside a nucleus。 This exotic state may reveal how mass is generated, suggesting that particles can weigh less when surrounded by dense nuclear matter。 The findings support long-standing theories about how the vacuum of space i
New experiments suggest that freezing and thawing on early Earth may have helped primitive cell-like structures grow and evolve。 Tiny lipid bubbles behaved very differently depending on their membrane makeup—some fused into larger compartments and captured DNA more efficiently。 These fusion events could have mixed key molecules, setting the stage f
This article summarizes technical advances contained in the fifth major release of the Q-Chem quantum chemistry program package, covering developments since 2015. A comprehensive library of exchange-correlation functionals, along with a suite of correlated many-body methods, continues to be a hallmark of the Q-Chem software. The many-body methods include novel variants of both coupled-cluster and configuration-interaction approaches along with methods based on the algebraic diagrammatic construction and variational reduced density-matrix methods. Methods highlighted in Q-Chem 5 include a suite of tools for modeling core-level spectroscopy, methods for describing metastable resonances, methods for computing vibronic spectra, the nuclear-electronic orbital method, and several different energy decomposition analysis techniques. High-performance capabilities including multithreaded parallelism and support for calculations on graphics processing units are described. Q-Chem boasts a community of well over 100 active academic developers, and the continuing evolution of the software is supported by an "open teamware" model and an increasingly modular design.
Iridium is the main element in modern catalysts for the oxygen evolution reaction (OER) in proton exchange membrane water electrolyzers (PEMWE), which is predominantly due to its relatively good activity and tolerable stability in harsh PEMWE conditions. Limited abundance of iridium, however, poses limitations on widespread applications of these devices, in particular in the large scale conversion and storage of renewable energy. In this work we investigate if the electrocatalytic performance of iridium can be fine-tuned by thermal treatment of catalysts at different temperatures. The OER activity and the dissolution of two different iridium electrodes, viz. (a) flat metallic iridium surfaces prepared by electron beam physical vapor deposition (EBPVD) and (b) electrochemically prepared porous hydrous iridium oxide films (HIROF) are studied. The range of applied annealing temperatures is 100 C-600 C, with a general trend of decreasing activity and increasing stability the higher the temperature. Numerous peculiarities in the trend are however observed. These are discussed considering variations of oxide structure, morphology and electronic conductivity.
Modelling the electrolyte at the electrochemical interface remains a major challenge in ab initio simulations of charge transfer processes at surfaces. Recently, the development of hybrid polarizable continuum models/ab initio models have allowed for the treatment of solvation and electrolyte charge in a computationally efficient way. However, challenges remain in its application. Recent literature has reported that large cell heights are required to reach convergence, which presents a serious computational cost. Furthermore, calculations of reaction energetics require costly iterations to tune the surface charge to the desired potential. In this work, we present a simple capacitor model of the interface that illuminates how to circumvent both of these challenges. We derive a correction to the energy for finite cell heights to obtain the large cell energies at no additional computational expense. We furthermore demonstrate that the reaction energetics determined at constant charge are easily mapped to those at constant potential, which eliminates the need to apply iterative schemes to tune the system to a constant potential. These developments together represent more than an order of magnitude reduction of the computational overhead required for the application of polarizable continuum models to surface electrochemistry.
Triplet-triplet annihilation photon upconversion (TTA-UC) is a process in which low-energy light is transformed into light of higher energy. During the last two decades, it has gained increasing attention due to its potential in, e.g., biological applications and solar energy conversion. The highest efficiencies for TTA-UC systems have been achieved in liquid solution, owing to that several of the intermediate steps require close contact between the interacting species, something that is more easily achieved in diffusion-controlled environments. There is a good understanding of the kinetics dictating the performance in liquid TTA-UC systems, but so far, the community lacks cohesiveness in terms of how several important parameters are best determined experimentally. In this perspective, we discuss and present a "best practice" for the determination of several critical parameters in TTA-UC, namely triplet excited state energies, rate constants for triplet-triplet annihilation ([Formula: see text]), triplet excited-state lifetimes ([Formula: see text]), and excitation threshold intensity ([Formula: see text]). Finally, we introduce a newly developed method by which [Formula: see text], [Formula: see text], and [Formula: see text] may be determined simultaneously using the same set of time-resolved emission measurements. The experiment can be performed with a simple experimental setup, be ran under mild excitation conditions, and entirely circumvents the need for more challenging nanosecond transient absorption measurements, a technique that previously has been required to extract [Formula: see text]. Our hope is that the discussions and methodologies presented herein will aid the photon upconversion community in performing more efficient and manageable experiments while maintaining-and sometimes increasing-the accuracy and validity of the extracted parameters.
The work herein reports on studies aimed at exploring the correlation between electrolyte volume and electrochemical performance of full cell, pouch-cells consisting of graphite/ Li<sub>1.02</sub>Ni<sub>0.50</sub>Mn<sub>0.29</sub>Co<sub>0.19</sub>O<sub>2</sub> (NMC-532) as the electrodes and 1.2 M LiPF<sub>6</sub> in ethylene carbonate:ethylmethyl carbonate (EC:EMC) as the electrolyte. In addition, it is demonstrated that a minimum electrolyte volume factor of 1.9 times the total pore volume of cell components (cathode, anode, and separator) is needed for long-term cyclability and low impedance. Less electrolyte results in an increase of the measured Ohmic resistances. Increased resistance ratios for charge transfer and passivation layers at cathode, relative to initial values, were 1.5 2.0 after 100 cycles. At the cathode, the resistance from charge transfer was 2-3 times higher than for passivation layers. Lastly, differential voltage analysis showed that anodes were less delithiated after discharging as the cells were cycled.