A5062117742- Advanced Chemical Physics Studies
- Machine Learning in Materials Science
- Metal-Organic Frameworks: Synthesis and Applications
- X-ray Diffraction in Crystallography
- Crystallography and molecular interactions
- Magnetism in coordination complexes
- Chemical Thermodynamics and Molecular Structure
- Catalysis and Oxidation Reactions
- High-pressure geophysics and materials
- Crystallization and Solubility Studies
- Organic and Molecular Conductors Research
- Enhanced Oil Recovery Techniques
- Inorganic Chemistry and Materials
- Computational Drug Discovery Methods
- Molecular Junctions and Nanostructures
- Quantum, superfluid, helium dynamics
- Inorganic Fluorides and Related Compounds
- Atomic and Subatomic Physics Research
- Spectroscopy and Quantum Chemical Studies
- History and advancements in chemistry
- Synthesis and characterization of novel inorganic/organometallic compounds
- Natural Language Processing Techniques
- Organometallic Complex Synthesis and Catalysis
- Semiconductor materials and interfaces
- Physics of Superconductivity and Magnetism
Taiwan Semiconductor Manufacturing Company (United States)
2022-2025
Stanford University
2021-2022
Interface (United States)
2021-2022
SLAC National Accelerator Laboratory
2020-2022
Central Michigan University
2018-2020
Institute of Theoretical Physics
2015-2018
Technische Universität Dresden
2015-2018
TU Bergakademie Freiberg
2015
Massachusetts Institute of Technology
2014
Harvard University
2013
The virtual high-throughput screening framework of the Harvard Clean Energy Project allows for computational assessment candidate structures organic electronic materials – in particular photovoltaics at an unprecedented scale. We report most promising compounds that have emerged after studying 2.3 million molecular motifs by means 150 density functional theory calculations. Our top candidates are analyzed with respect to their structural makeup order identify important building blocks and...
The Fermi‐Löwdin orbital self‐interaction correction (FLO‐SIC) methodology is applied to atoms and molecules from the standard G2‐1 test set. For first time FLO‐SIC results for GGA‐type PBE functional are presented. In addition, examples where like any proper SIC provides qualitative improvements compared DFT functionals discussed in detail: dissociation limit , step‐wise linearity behavior fractional occupation, as well significant reduction of error static polarizabilities. Further,...
First principles calculations using density functional theory (DFT) have been performed to investigate the electronic and magnetic properties of DUT-8(Ni) (DUT - Dresden University Technology). This flexible metal-organic framework (MOF) exists in two crystalline forms: DUT-8(Ni)open DUT-8(Ni)closed. To identify energetically favoured ordering, states (DOS) energy difference between a low-spin (LS) high-spin (HS) coupling ΔELS-HS for those structures computed. Calculations on supercells...
Ports are clearly important to the national and global economies. Several high profile events highlight need not only harden ports but decrease recovery times when failures do occur increase resilience of system as a whole. Our research suggests that disruptions with regular frequency and, outliers removed, range from 6 20 days in duration. Furthermore, we find key commodity classes, such chemicals food farm products may be especially sensitive those due geographic cargo concentrations....
We analyze the effect of removing self-interaction error on magnetic exchange couplings using Fermi-Löwdin orbital correction (FLOSIC) method in framework density functional theory (DFT). compare obtained from self-interaction-free FLOSIC calculations with local spin approximation (LSDA) several widely used DFT realizations and wave function based methods. To this end, we employ linear H-He-H model system, six organic radical molecules, [Cu2Cl6]2- as representatives different types...
Semi-local approximations to the density functional for exchange-correlation energy of a many-electron system necessarily fail lobed one-electron densities, including not only familiar stretched densities but also less closely-related noded ones. The Perdew-Zunger (PZ) self-interaction correction (SIC) semi-local approximation makes that exact all ground- or excited-state and accurate bonds. When minimization PZ total is made over real localized orbitals, orbital can be noded, leading errors...
The self-interaction error (SIE) is one of the major drawbacks practical exchange-correlation functionals for Kohn–Sham density functional theory. Despite this, use methods that explicitly remove SIE from approximate scarce in literature due to their relatively high computational cost and lack consistent improvement over standard modern functionals. In this article we assess performance a novel approach recently proposed by Pederson, Ruzsinszky, Perdew [J. Chem. Phys. 2014, 140, 121103]...
The NMR chemical shift of the xenon isotope 129Xe inside metal-organic frameworks (MOFs) UiO-66 and UiO-67 (UiO - University Oslo) has been investigated both with density functional theory (DFT) in situ high-pressure measurements. experiments reveal a decrease total comparing larger isoreticular MOF (UiO-67) smaller one (UiO-66), even though may expect an increase due to higher amount adsorbed Xe atoms. We are able calculate contributions individually. This allows us evaluate different pores...
We present an interpretation of Fermi‐orbital descriptors (FODs) and argue that these carry chemical bonding information. show a bond order derived from FODs agrees well with reference values, highlight optimized FOD positions used within the Fermi‐Löwdin orbital self‐interaction correction (FLO‐SIC) method correspond to expectations Linnett's double‐quartet theory, which is extension Lewis theory. This observation independent underlying exchange‐correlation functional, shown using local...
We present pyflosic, an open-source, general-purpose python implementation of the Fermi–Löwdin orbital self-interaction correction (FLO-SIC), which is based on simulation chemistry framework (pyscf) electronic structure and quantum code. Thanks to pyscf, pyflosic can be used with any kind Gaussian-type basis set, various kinds radial angular quadrature grids, all exchange-correlation functionals within local density approximation, generalized-gradient approximation (GGA), meta-GGA provided...
We present a first principles study of low-spin (LS)/high-spin (HS) screening for 3d metal centers in the organic framework (MOF) DUT-8(Ni).
The Fermi-Löwdin orbital self-interaction correction (FLOSIC) formalism is a novel method for implementing the Perdew-Zunger (PZ-SIC) in density functional theory calculations. In this paper we consider how use of Fermi orbitals affects total energies and other calculated properties compared to standard approach PZ-SIC that utilizes localization equation conditions. We directly compare results two methods using identical basis sets numerical techniques calculations isolated atoms up Kr large...
The Perdew-Zunger (PZ) self-interaction correction (SIC) is an established tool to correct unphysical behavior in density functional approximations. Yet, the PZ-SIC well-known sometimes break molecular symmetries. An example of this benzene molecule, for which predicts a symmetry-broken electron and geometry, since method does not describe two possible Kekulé structures on even footing, leading local minima [Lehtola et al.
We derived, implemented, and thoroughly tested the complete analytic expression for atomic forces, consisting of Hellmann-Feynman term Pulay correction, Fermi-Löwdin orbital self-interaction correction (FLO-SIC) method. Analytic forces are shown to be numerically accurate through an extensive comparison obtained from finite differences. Using equilibrium structures a small set molecules were obtained. This work opens possibility routine free geometrical relaxations using FLO-SIC © 2018 Wiley...
Sun et al. [J. Chem. Phys. 144, 191101 (2016)] suggested that common density-functional approximations (DFAs) should exhibit large energy errors for excited states as a necessary consequence of orbital nodality. Motivated by self-interaction corrected calculations on many-electron systems, we continue their study with the exactly solvable 1s, 2p, and 3d 36 hydrogenic one-electron ions (H-Kr35+) demonstrate self-consistent state-of-the-art DFAs indeed 2p states. We consider 56 functionals at...
The behavior of electrons during bond formation and breaking cannot commonly be accessed from experiments. Thus, perception is often based on chemical intuition or rule-based algorithms. Utilizing computational chemistry methods, we present intrinsic descriptors for the Diels-Alder reaction, allowing an automatic perception. We show that these are available localized orbitals self-interaction correction calculations, e.g., Fermi-orbital descriptors. proposed allow a sparse, simple,...
Abstract The Fermi-Löwdin orbital (FLO) approach to the Perdew-Zunger self-interaction correction (PZ-SIC) density functional theory (DFT) is described and an improved problem of optimizing Fermi-orbitals in order minimize DFT-SIC total energy introduced. To illustrate use FLO-SIC method, results are given for several applications involving problems where errors pronounced.
Density functional theory (DFT)-based methods often significantly underpredict chemical reaction barriers compared with experiments because of the tendency DFT to overstabilize transition states stretched bonds due impact unphysical electron self-interaction. However, many reactions have early or late where state geometry closely resembles reactants products, respectively. The role self-interaction in those cases is not known. Here we compare performance and without correction (SIC) for...
Reliable predictions of surface chemical reaction energetics require an accurate description both chemisorption and physisorption. Here, we present empirical approach to simultaneously optimize semi-local exchange nonlocal correlation a density functional approximation improve these energetics. A combination reference data for solid bulk, surface, gas-phase chemistry physical exchange-correlation model constraints leads the VCML-rVV10 functional. Owing variety training data, applicability...
We present the results of our density functional theory study ${\text{Co}}_{n}{\text{Mo}}_{m}$ nanoclusters with $n+m=x$ and $2\ensuremath{\le}\ifmmode\times\else\texttimes\fi{}\ensuremath{\le}6$ atoms on all-electron level using generalized gradient approximation. The discussion properties pure cobalt molybdenum cluster is followed by an analysis respective mixed clusters each size $x$. found that magnetic moment a given mainly determined Co content increases increasing $n$. anisotropy...
Abstract The predictive power of density functional theory for materials properties can be improved without increasing the overall computational complexity by extending generalized gradient approximation (GGA) electronic exchange and correlation to functionals depending on kinetic energy in addition charge its gradient, resulting a meta‐GGA. Here, we propose an empirical meta‐GGA model that is based both physical constraints experimental quantum chemistry reference data. optimized MCML...
Fermi-Löwdin orbitals (FLOs) are a special set of localized orbitals, which have become commonly used in combination with the Perdew-Zunger self-interaction correction (SIC) FLO-SIC method. The FLOs obtained for occupied by specifying classical position each electron. These positions known as Fermi-orbital descriptors (FODs), and they clear relation to chemical bonding. In this study, we show how FODs can be initialize, interpret, justify SIC solutions common picture, both within traditional...
New Ni<sup>II</sup>formate complexes were synthesized and characterized to exhibit low decomposition temperatures produce pure metallic nickel.
The pressure dependence of the 129Xe chemical shift in metal-organic frameworks (MOFs) UiO-66 and UiO-67 (UiO - University Oslo) has been investigated using both theory experiment. resulting isotherms were analyzed with a theoretical approach based on model systems (as proposed by K. Trepte, J. Schaber, S. Schwalbe, F. Drache, I. Senkovska, Kaskel, Kortus, E. Brunner G. Seifert, Phys. Chem. Phys., 2017, 19, 10020-10027) experimental NMR measurements at different pressures. All investigations...