Flatiron Health (United States)

High-performance parallel implementation of spin-free high-order coupled-cluster theories

High-order coupled-cluster theories with iterative triples (CCSDT), perturbative quadruples [CCSDT(Q)], and iterative quadruples (CCSDTQ) provide benchmark-quality correlation energies, but their steep computational scalings, O(N8), O(N9), and O(N10), together with the large memo...

Distilling First-Principles Accuracy into Compact Machine Learning Potentials for Condensed-Phase Chemistry

Abstract Accurate machine learning interatomic potentials (MLIPs) have made first-principles-quality potential energy surfaces increasingly accessible for condensed-phase chemistry, but their inference cost can still limit the sampling needed to compute experimentally relevant ob...

Adsorption energies and decomposition barrier heights for ethylene carbonate on the surface of lithium from cluster-based quantum chemistry

For ethylene carbonate on the (100) surface of lithium, we calculate the adsorption energy in two binding motifs and the barrier height for a ring-opening decomposition reaction. We validate a scheme for producing results in the thermodynamic limit by correcting results obtained...

2D theoretically twistable material database

The study of twisted two-dimensional (2D) materials, in which twisting layers create moiré superlattices, has created opportunities for investigating topological phases and strongly correlated physics. The broader potential of a seemingly infinite set of twistable 2D materials re...

Two-dimensional topological quantum chemistry and catalog of topological materials

Two-dimensional (2D) topological materials host symmetry-protected, disorder-robust edge states central to quantum technologies. Yet they remain scarce compared with their 3D counterparts. We adapted the topological quantum chemistry formalism to layer groups and studied the band...

STAR_Lite: a stellarator designed to experimentally validate non-resonant divertors

The non-resonant divertor (NRD) offers a promising exhaust solution for stellarators, combining topological simplicity with resilience to magnetic field perturbations. To experimentally validate the robustness of NRDs in a quasi-axisymmetric (QA) configuration, we introduce STAR_...

Beyond the Virial Expansion: Microscopic Origins of Partial Molar Volumes in LiCl Solutions

Abstract Although electrolyte density measurements have been reported for over a century, employing them to determine accurate partial molar volume (PMV) profiles as a function of salt concentration has remained elusive. Obtaining such curves requires precise density measurements...

Improving the accuracy of fixed-node diffusion Monte Carlo for non-covalent interactions

Diffusion quantum Monte Carlo (DMC) and coupled cluster theory [CCSD(T)] are widely used benchmark methods for noncovalent interactions (NCIs). However, recent studies have reported notable discrepancies for several hydrogen-bonded and dispersion-dominated systems, raising questi...

Unidirectional flow from continuous broken symmetries

Locally broken symmetries are used across fields to transport matter, particles, and information in preferential directions. Beyond local mechanisms, spatially distributed nonlinearities in crystalline media have enabled nonreciprocal transport, a rectification mechanism that ope...

The Python simulations of chemistry framework: 10 years of an open-source quantum chemistry project

Over the past decade, the Python-based Simulations of Chemistry Framework (PySCF) has developed into a widely used open-source platform for electronic-structure theory and quantum chemical method development. This article reviews the major advances since the previous overview in...

Dust Substructures and Line Perturbations driven by a Forming Planet in J16120

Abstract Hints of planet formation have been independently reported within the gap of the disc around 2MASS J16120668-301027 from millimetre continuum, infrared, and Hα observations. In this work, we present new evidence for ongoing planet formation based on Atacama Large Millime...

Neural network–augmented Pfaffian wave-functions for scalable simulations of interacting fermions

Developing accurate numerical methods for strongly interacting fermions is crucial for improving our understanding of various quantum many-body phenomena, especially unconventional superconductivity. Recently, neural quantum states have emerged as a promising approach for studyin...

Self-consistent vertex corrected GW with static and dynamic screening using tensor hypercontraction: Assessment of molecular charged excitations

We investigate self-consistent vertex corrections to the GW self-energy for ionization potentials (IPs) and electron affinities (EAs). We benchmark IPs against ΔCCSD(T) references in the G0W0Γ29 and GW100 sets and compare GW100 EAs with EOM-CCSD references. Because many anions ar...

Optically induced Faraday–Goldstone waves

Faraday waves, typically observed in driven fluids, result from the confluence of nonlinearity and parametric amplification. Here we show that optical pulses can generate analogous phenomena that persist much longer than the pump time-scales in ordered quantum solids. We present...

The Star Formation History and Evolution of the Ultra-Diffuse M81 Satellite F8D1

Abstract We present deep Hubble Space Telescope (HST) imaging of one of the nearest ultra-diffuse galaxies (UDGs) outside of the Local Group: F8D1, a satellite of M81 known to be tidally disrupting. UDGs are an enigmatic and diverse population, with evolutionary pathways ranging...

Testing electron–photon exchange–correlation functional performance for many-electron systems under weak and strong light–matter coupling

We present results for a photon-free exchange–correlation functional within the local density approximation (pxcLDA) for quantum electrodynamics density functional theory (QEDFT), which efficiently describes the electron density of many-electron systems across weak to strong ligh...

Non-ideal MHD and protostellar feedback effects on disk formation and evolution in numerical simulations of star cluster formation

Abstract While recent surveys have resolved hundreds of nearby protostellar disks, numerical simulations assuming ideal magnetohydrodynamics (MHD) have historically struggled to achieve disk formation due to efficient angular momentum removal by magnetic torques. Non-ideal MHD ef...