State Energy Research Articles

Multiscale Mass Transport Across Membranes: From Molecular Scale to Nanoscale to Micron Scale.

Multiscale mass transport across membranes occurs ubiquitously in biological systems but is difficult to achieve and long-sought-after in abiotic systems. The multiscale transmembrane transport in abiotic systems requires the integration of multiscale transport channels and energy ergodicity, making multiscale mass transport a significant challenge. Herein, emulsion droplets with cell-like confinement are used as the experimental model, and multiscale mass transport is achieved from molecular scale to nanoscale to micron scale, reproducing rudimentary forms of cell-like transport behaviors. By adjustment of the magnetic dipole interactions between adjacent superparamagnetic nanoparticles (MNPs), the assembled structure at the interface of emulsion droplets is successfully modified, which constructs transport channels of various scales at the interface. Simultaneously, the assembly process of MNPs induces self-emulsification, which increases entropy and further reduces Gibbs free energy, ultimately realizing multiscale mass transport that evolves in time visiting all possible microscopic states (energy ergodicity). This work represents the comprehensive identification and realization of a multiscale transmembrane transport in abiotic droplet systems, which offers opportunities for the development of high-order cell-like characteristics in emulsion droplet-based communities, synthetic cells, microrobots, and drug carriers.

Diagonalizing Bose Gases in the Gross–Pitaevskii Regime and Beyond

We present a novel approach to the Bogoliubov theory of dilute Bose gases, allowing for an elementary derivation of the celebrated Lee–Huang–Yang formula in the Gross–Pitaevskii regime. Furthermore, we identify the low lying excitation spectrum beyond the Gross–Pitaevskii scaling, extending a recent result (Brennecke et al. in Rev Math Phys 34, 2022) to significantly more singular scaling regimes. Finally, we provide an upper bound on the ground state energy in the Gross–Pitaevskii regime that captures the correct expected order of magnitude beyond the Lee–Huang–Yang formula.

Systematic Investigation of Electronic States and Bond Properties of LnO, LnO+, LnS, and LnS+ (Ln = La-Lu) by Spin-Orbit Multiconfiguration Perturbation Theory.

The electronic structures of lanthanide monoxides (LnO/LnO+) and monosulfides (LnS/LnS+) for all lanthanide series elements (Ln = La-Lu) have been systematically analyzed with sophisticated quantum chemical calculations. The ground electronic configuration has been determined to be Ln 4fn6s1 or 4fn+1 for the neutral molecules and Ln 4fn for the cations. The low-lying energy states resulting from spin-orbit coupling and ligand field effects have been resolved using spin-orbit multiconfiguration quasi-degenerate second-order perturbation theory calculations. The ionization energies of LnO (5.20-7.06 eV) are about 0.3-2.2 eV lower than those of LnS (5.54-9.22 eV) due to the difference in the Ln 6s and 4f orbital energies from which an electron is removed during the ionization process. The bond dissociation energies (BDEs) have been computed by the state-averaged general multiconfigurational perturbation theory and the completely renormalized coupled-cluster [CR-CC(2,3)] methods. The BDEs are highly dependent on the lanthanide elements as several factors of the lanthanides affect the bond dissociation. The calculated bond lengths and energies agree well with available experimental values and are systematically predicted for the series of lanthanide monoxides and monosulfides where experimental values are not available. Furthermore, the LS terms of low-lying energy states and their corresponding bond properties have been clarified in detail to systematize the similarities and differences of the lanthanide compounds.

Noninvertible Symmetry-Resolved Affleck-Ludwig-Cardy Formula and Entanglement Entropy from the Boundary Tube Algebra

We derive a refined version of the Affleck-Ludwig-Cardy formula for a 1+1D conformal field theory, which controls the asymptotic density of high energy states on an interval transforming under a given representation of a noninvertible global symmetry. We use this to determine the universal leading and subleading contributions to the noninvertible symmetry-resolved entanglement entropy of a single interval. As a concrete example, we show that the ground state entanglement Hamiltonian for a single interval in the critical double Ising model enjoys a Kac-Paljutkin H8 Hopf algebra symmetry when the boundary conditions at the entangling points are chosen to preserve the product of two Kramers-Wannier symmetries, and we present the corresponding symmetry-resolved entanglement entropies. Our analysis utilizes recent developments in symmetry topological field theories. Published by the American Physical Society 2024

Excited states from GW/BSE and Hartree-Fock theory: Effects of polarizability and transition type on accuracy of excited state energies.

GW and Bethe-Salpeter equation (BSE) methods are used to calculate energies of excited states of organic molecules in the Quest-3 database [Loos et al., J. Chem. Theory Comput. 16, 1711 (2020)]. The self-energy in the GW approximation is conventionally calculated using the RPA polarizability. Inclusion of a screened electron-hole interaction in the polarizability was recently shown to improve predictions of experimental ionization energies in organic molecules [C. H. Patterson, J. Chem. Theory Comput. 20, 7479 (2024)]. Self-energies from RPA or screened time-dependent Hartree-Fock (TDHF) polarizabilities in the GW/BSE method are used to calculate 141 singlet excited states in Quest-3. Theoretical best estimate excited state energies from the CC3 coupled cluster method and aug-cc-pVTZ basis sets are used to benchmark GW/BSE and CIS calculations using the same molecular geometries and basis sets. Differences between GW/BSE or CIS excited state energies and best estimate values show that there are systematic variations in the accuracies of excited state energies classified as ππ*, nπ*, πR (Rydberg), or nR character. The origin of these variations is the accuracy of self-energies of states of nonbonding vs π bonding character. In particular, N or O lone pair states require large self-energy corrections owing to strong orbital relaxation in the localized hole state, while π states have smaller corrections. Self-energies from a screened TDHF vs RPA polarizability are typically over(under)estimated for nonbonding states, leading to under(over)estimation of energies of excited states of nπ* or nR character.

New York State Climate Impacts Assessment Chapter 06: Energy.

Energy plays an integral role in New Yorkers' lives. It powers the economy, moves people and goods, keeps homes and workplaces at a livable temperature, and runs critical infrastructure that keeps people healthy and safe. Reliable energy systems are easy to take for granted, but many aspects of these systems are vulnerable to weather and climate hazards. This chapter discusses how climate change is affecting and will increasingly affect New York State's energy supply, delivery, and end uses. It provides insights into current and future climate vulnerabilities as New York's energy system transitions to clean energy sources. This assessment also highlights opportunities to adapt current and future energy systems and to build resilience to climate impacts.

Disentangling Structural Domains in Solution‐Processed 2D Lead Halide Perovskite by Transient Absorption Spectroscopy

Abstract2D lead halide perovskites (LHPs) exhibit outstanding optoelectronic properties, making them utilized in various emerging applications. Understanding their fundamental properties is urgent for improving device performance. Here, the structural domains in 2D PEA2MAn‐1PbnI3n+1 films are studied by temperature‐dependent transient absorption (TA) measurements. For <n> = 1 film at low temperatures, the ground state bleach (GSB) shows obvious splitting when the high‐energy state is resonantly excited, whereas only one GSB exists under low‐energy resonant excitation, indicating that the two split energy states correspond to different structural domains. For <n> = 2 film, similar phenomena are observed, but the energy level difference between the two domains is decreased. With further increase of the inorganic layers number, the two domains can no longer be distinguished. In addition, by changing the organic cations, it is demonstrated that the two structural domains originate from distortions in the inorganic PbI6 octahedral frames. Finally, the possibility that the two energy states are from the formation of polaron states is ruled out by TA measurement on CsPbBr3 QDs. The results provide new insights into the structural domain properties of 2D LHPs, which directly influence the suitability of these materials for future optoelectronic devices.

Initial State Preparation for Quantum Chemistry on Quantum Computers

Quantum algorithms for ground-state energy estimation of chemical systems require a high-quality initial state. However, initial state preparation is commonly either neglected entirely, or assumed to be solved by a simple product state like Hartree-Fock. Even if a nontrivial state is prepared, strong correlations render ground-state overlap inadequate for quality assessment. In this work, we address the initial state preparation problem with an end-to-end algorithm that and the quality of initial states, accomplishing the latter with a new metric—the energy distribution. To be able to prepare more complicated initial states, we introduce an implementation technique for states in the form of a sum of Slater determinants that exhibits significantly better scaling than all prior approaches. We also propose low-precision quantum phase estimation (QPE) for further state quality refinement. The complete algorithm is capable of generating high-quality states for energy estimation, and is shown in select cases to lower the overall estimation cost by several orders of magnitude when compared with the best single product state ansatz. More broadly, the energy distribution picture suggests that the goal of QPE should be reinterpreted as generating improvements compared to the energy of the initial state and other classical estimates: such an improvement can still be achieved even if QPE does not project directly onto the ground state. Finally, we show how the energy distribution can help in identifying potential quantum advantage. Published by the American Physical Society 2024

Charge Transfer and Retention in 2D Passivated Perovskite-C60 Systems.

2D perovskites and organic ligands are often implemented as passivating interlayers in perovskite solar cells. Herein, five such passivates are evaluated by using time-resolved spectroscopy to study the carrier dynamics at the perovskite-C60 interface. The impact of passivation on factors such as charge transfer rate, charge retention in the acceptor layers, surface recombination, and uniformity are mapped onto the solar cell performance. The charge transfer was found to take place in tens of nanoseconds, and the charge retention without any passivate lasted a few hundred nanoseconds. The passivate that produced the best solar cells, ethylenediammonium iodide, extended the charge retention time up to one microsecond, which significantly increased the open-circuit voltage. It also had the best uniformity and hence least variance in power conversion efficiency. Curiously, it did not merely adjust surface energy states to enhance charge transfer but also extracted charges by itself without the C60, resulting in higher short-circuit current.

Криза прав власності у розподільчому сегменті ринку природного газу України

During the time of independent Ukraine's existence, the authorized state bodies have not developed effective mechanisms for the use of state-owned gas distribution networks by private operators. Despite the state being the de facto owner of these networks, it was unable to receive appropriate compensation for their operation, and no incentives were created for the modernization of the networks. Meanwhile, private operators were motivated to consistently report a decrease in the value of such assets. Another complex issue, in terms of the efficiency and fairness of managing the gas distribution system, is the ownership of networks built with consumer funds and transferred to gas distribution network operators for operation. The lack of clear understanding regarding the ownership of gas transportation networks results in significant wear and tear of the networks and substantial production and technical losses. Gas transmission operators are not interested in making significant investments in the renewal and development of networks, as they do not own them, and there are no other obligations that could incentivize such activities. The state does not receive any income from the use of state property by economic entities. In the context of the Russian-Ukrainian war, the issue of property rights and further investments in the development of gas distribution networks has once again come to the forefront. The need to adapt the energy system to the new challenges of the war necessitates the formation of a decentralized model of the national energy system. In the gas sector, this means that at the local level, local self-government bodies will need to take the initiative in implementing small energy projects to meet the energy supply demands of the local population, such as the construction of various types of gas cogeneration plants. The construction of such projects will require the adaptation and development of the existing gas distribution networks to meet new requirements. The formation of a new decentralized model of the national energy network is impossible without resolving the old problems related to the ownership rights of gas distribution networks and establishing a market-based tariff setting for the operation of these networks. The article analyzes the theoretical prerequisites for the emergence of the property rights crisis in the distribution segment of the natural gas market based on the theory of property rights. Through retrospective analysis, the main flaws in the state energy policy in the management of state-owned gas distribution networks are identified, which led to the current property rights crisis and increased transaction costs among entities in Ukraine’s natural gas market. Based on the obtained results and taking into account foreign experience in the privatization and regulation of the economic activities of gas distribution operators, the author proposes various ways to address the problems of managing property rights for the distribution gas networks.

An Organic EnT Photocatalyst 4CzMeBN and the Application in the Synthesis of cis-Fused Azetidines.

A powerful EnT photocatalyst 4CzMeBN has been developed and utilized in the synthesis of cis-fused azetidines via dearomative [2+2] cycloaddition under visible light. The photocatalyst 4CzMeBN is a donor-acceptor cyanoarene and features high triplet state energy and long lifetime of triplet state, which would be an alternative to widely used EnT photocatalyst Ir[dF(CF3)ppy]2(dtbbpy)PF6. The photochemical [2+2] cycloaddition provides a facile method to synthesize valuable dihydroisoquinolone-fused azetidines with high efficiency.

Exploring the Influence of Approximations for Simulating Valence Excited X-ray Spectra.

First-principles simulations of excited-state X-ray spectra are becoming increasingly important to interpret the wealth of electronic and geometric information contained within femtosecond X-ray absorption spectra recorded at X-ray Free Electron Lasers (X-FELs). However, because the transition dipole matrix elements must be calculated between two excited states (i.e., the valence excited state and the final core excited state arising from the initial valence excited state) of very different energies, this can be challenging and time-consuming to compute. Herein using two molecules, protonated formaldimine and cyclobutanone, we assess the ability of n-electron valence-state perturbation theory (NEVPT2), equation-of-motion coupled-cluster theory (EOM-CCSD), linear-response time-dependent density functional theory (LR-TDDFT) and the maximum overlap method (MOM) to describe excited state X-ray spectra. Our study focuses in particular on the behavior of these methods away from the Franck-Condon geometry and in the vicinity of important topological features of excited-state potential energy surfaces, namely, conical intersections. We demonstrate that the primary feature of excited-state X-ray spectra is associated with the core electron filling the hole created by the initial valence excitation, a process that all of the methods can capture. Higher energy states are generally weaker, but importantly much more sensitive to the nature of the reference electronic wave function. As molecular structures evolve away from the Franck-Condon geometry, changes in the spectral shape closely follow the underlying valence excitation, highlighting the importance of accurately describing the initial valence excitation to simulate the excited-state X-ray absorption spectra.

Anisotropic Dielectric Screened Range-Separated Hybrid Density Functional Theory Calculations of Charge Transfer States across an Anthracene-TCNQ Donor-Acceptor Interface.

A density functional theory framework is developed to study electronic excited states affected by an anisotropic dielectric environment. In particular, an anisotropic dielectric screened range-separated hybrid (SRSH[r]) functional is defined and combined with an anisotropic polarizable continuum model (PCM) implemented through a generalized Poisson equation solver. We develop the SRSH-PCM(r) approach and use it to quantify the effect of anisotropy on an excited charge transfer (CT) state energy. In particular, the dielectric interface effect on the CT state within a donor-acceptor molecular complex of antrancene and tetracyanoquinodimethane is studied. The donor-acceptor complex and the dielectric interface are used to represent the interface between thin films consisting of these materials. We report the effect of such a dielectric interface on the energy of a CT and follow its dependence on the donor-acceptor distance. We also benchmark the anisotropy-affected energy by comparing to homogeneous dielectric calculated energies. Due to the planar interface, the anisotropic energies are expected to to match with those obtained based on isotropic calculations of the larger dielectric constant at large enough distances. The approach is applicable, in general, to more complicated dielectric constant distributions as expected to be found in actual interfaces of such thin films or in other systems, for example, for CT processes within photosystems.

On the Schrödinger–Bopp–Podolsky system: Ground state and least energy nodal solutions with nonsmooth nonlinearity

In this paper, we investigate a new class of Schrödinger–Bopp–Podolsky systems. Using minimization techniques and the concept of generalized subdifferentials, we establish the existence of a ground state solution with a fixed sign as well as a least energy nodal solution for the system. Furthermore, we demonstrate that the energy of the nodal solution is precisely twice that of the ground state solution.

Carbonate-mediated Mars-van Krevelen mechanism on CuxO/CeO2 catalysts for boosting CO oxidation

Copper-cerium-based catalysts have gained considerable attention for their excellent performance in low-temperature CO oxidation applications. In this context, the carbonate-mediated Mars-van Krevelen (M−vK) pathway stands out as a promising route for enhancing catalytic performance. Herein, we prepared three CuxO/CeO2 nanocatalysts with varying copper content using Cu2O nanocrystals (Cu2O NCs) and Ce-BTC metal–organic frameworks (MOFs) as dual precursors. The optimal catalyst exhibits excellent performance (T100 value of 110 °C) comparable to the precious metal catalyst. Through integrating in-depth experimental results and density functional theory (DFT) calculations, we reveal the intricate interplay of interfacial synergistic catalysis and carbonate-mediated M−vK mechanisms, confirming that carbonate species generated under mild conditions significantly promote CO oxidation on CuxO/CeO2 nanocatalysts. Based on the comparison of the transition state (TS) energy barrier between the traditional and the carbonate-mediated M−vK mechanism reaction paths, we found that carbonate species is easier to form and establish the rate-determining step (viz., carbonate → CO2, the energy barrier of 1.51 eV). This study sheds light on the importance of carbonate species in modulating the catalytic behaviour of copper-cerium catalysts and provides valuable insights for designing efficient catalysts for CO oxidation applications.

Studying evaporating black hole using quantum computation algorithms on IBM quantum processor

Analyzing complex quantum systems using quantum computational algorithms is one of the most promising applications of quantum computers. This study focuses on evaluating the performance of a custom variational ansatz in the Variational Quantum Eigensolver (VQE) algorithm compared to predefined ansatzes. To achieve this, we employ the evaporating black hole model as a test bed for our analysis. Using the VQE approach, which integrates quantum and classical computing techniques, we aim to minimize the energy expectation value of the Hamiltonian. By training the circuit parameters of a trial wave function as a parameterized quantum circuit, we determine the upper bound for the ground state energy and assess the optimal variational form. We define a custom ansatz for the VQE protocol and compare its performance with other predefined ansatzes. Additionally, we test the performance of three different classical optimizers to further understand their impact on the VQE algorithm’s efficiency and accuracy.

Investigation of the microstructural characteristics of laser-cladded Ti6Al4V titanium alloy and its corrosion behavior in simulated body fluid

Laser cladding technology has a wide range of potential industrial applications in the surface strengthening, repair and reuse of orthopedic implants. By employing this technique to conduct same-material surface restoration and enhancement on titanium alloys, it demonstrates significant developmental potential. However, the microstructure of laser additively manufactured titanium alloy differs significantly from that of traditional titanium alloys, which affects its corrosion resistance in human body fluids. To compare the corrosion resistance differences between the cladding layer and the substrate, this study investigates the microstructure of multi-pass laser cladding Ti6Al4V (TC4) titanium alloy and analyzes the corrosion morphology and corrosion products of the cladding layer in simulated body fluids (SBF). By comparing the electrochemical corrosion behavior of laser cladding with that of traditionally manufactured TC4, this research reveals the differences in corrosion resistance between the two titanium alloys. The research demonstrates that the microstructure of cladding primarily consists of prior-β grains and continuous grain boundary α phase, along with a complex basketweave structure composed of fine acicular α phase and lamellar α phase. Additionally, due to the complex thermal cycling process, the acicular α' colonies within the prior-β grains. These features enhance the cladding layer’s resistance to plastic deformation and increase microhardness, though with some uneven distribution. Interestingly, the TC4 cladding layer forms a porous passivation layer after corrosion, primarily composed of a TiO2 passivation film and deposits of hydroxyapatite and other phosphates. Due to the lower β-phase content, finer grains with higher energy states, and a greater proportion of high-angle grain boundaries (HAGBs) in the cladding layer, it exhibits higher electrochemical activity. As a result of these microstructural differences, the corrosion resistance of the TC4 cladding layer in SBF is inferior to that of TC4 manufactured using traditional techniques.

Dual-Band Electrochromic Supercapacitor Utilizing Metal-Organic Coordination Polymer with Multi-Redox Feature.

Electrochromic supercapacitors, which indicate energy states through optical color changes, are gaining significant attention for their potential in energy saving and recycling. In this study, a novel metal-organic coordination polymer (DTPB-MCP) is successfully synthesized using an N,N'-diphenyl-1,4-phenylenediamine (DTPB)-functionalized phenanthroline ligand. The resulting DTPB-MCP film demonstrated desirable electrochromic performance in both the visible light (ΔT:77.6% at 730nm) and near-infrared (ΔT: 49.2% at 1410nm) regions, as well as decent energy-storage capabilities (16.4mFcm- 2 at 0.1mAcm- 2), attributed to the presence of multiple redox centers. Furthermore, a hybrid electrochromic supercapacitor is also developed by combining DTPB-MCP with V₂O₅ (DTPB-MCP//V₂O₅), showcasing a significant optical contrast (47.6% at 750nm and 14.5% at 1420nm), an acceptable capacitance of 11.5mFcm- 2 with good rate performance, and impressive cycling stability (maintaining 81% of capacitance after 2750 charging/discharging cycles). In addition, >60% of electric energy can be reused to drive small household appliances during the bleaching process. The design principles outlined in this study offer valuable insights into the development of high-performance dual-band electrochromic energy-storage materials, highlighting their potential applications in energy recovery and reuse.

Interband and intraband transitions, as well as charge mobility in driven two-band model with electron-phonon coupling.

Interband and intraband transitions are fundamental concepts in the study of electronic properties of materials, particularly semiconductors and nanomaterials. These transitions involve the movement of electrons between distinct energy states or bands within a material. In addition, charge mobility is also a critical parameter in materials science and electronics. A thorough understanding of these transitions and mobility is critical for the development and optimization of advanced electronic and optoelectronic devices. In this study, we investigate the influence of external periodic drivings on interband and intraband transitions, as well as charge mobility, within a driven two-band model that includes electron-phonon coupling. These external periodic drivings can include a periodic laser field, a time-varying magnetic or electric field, or an alternating current voltage source. We have developed the Floquet surface hopping and Floquet mean field methods to simulate electronic dynamics under various drivings in both real and reciprocal spaces. Our findings demonstrate that periodic drivings can enhance interband transitions while suppressing intraband transitions. In addition, charge mobility is restrained by these external periodic drivings in the driven two-band model.

Ground State Energy Is Not Always Convex in the Number of Electrons.

We provide the first counterexample showing that the ground state energy of electrons in an external Coulomb potential is not always a convex function of the number of electrons. This convexity has been conjectured for decades and plays an important role in quantum chemistry. Our counterexample involves six nuclei with small fractional charges placed far apart. The ground state energy of 3 electrons is shown to be higher than the average of the energies for 2 and 4 electrons. We also show that the nuclei can bind 2 or 4 electrons, but not 3. This article raises the question of whether the energy convexity really holds for all possible molecules (with nuclei of integer charge).