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Concept

Crystal structure prediction

Publications associées (20)

Chemical Shift-Dependent Interaction Maps in Molecular Solids

David Lyndon Emsley, Manuel Cordova

Structure determinationof molecular solids through NMR crystallographyrelies on the generation of a comprehensive set of candidate crystalstructures and on the comparison of chemical shifts computed for thosecandidates with experimental values. Exploring t ...

AMER CHEMICAL SOC2023

Controlling the crystal structure of succinic acid via microfluidic spray-drying

Esther Amstad, Aysu Ceren Okur

Many properties of materials, including their dissolution kinetics, hardness, and optical appearance, depend on their structure. Unfortunately, it is often difficult to control the structure of low molecular weight organic compounds that have a high propen ...

ROYAL SOC CHEMISTRY2023

NMR Crystallography in the Big Data Era: New Methods and Applications Powered by Machine Learning

Manuel Cordova

Structure determination of materials is key to understanding their physical properties. While single-crystal X-ray diffraction is the gold standard for structures displaying long-range order, many materials of interest are polycrystalline and/or disordered ...

EPFL2023

Machine-learned interatomic potentials: Recent developments and prospective applications

William Curtin

High-throughput generation of large and consistent ab initio data combined with advanced machine-learning techniques are enabling the creation of interatomic potentials of near ab initio quality. This capability has the potential of dramatically impacting ...

Springer Heidelberg2023

Bootstrapping traceless symmetric O(N) scalars

Alessandro Vichi, Maria Refinetti, Marten Jan Reehorst

We use numerical bootstrap techniques to study correlation functions of traceless sym-metric tensors of O(N) with two indices ti j. We obtain upper bounds on operator dimen-sions for all the relevant representations and several values of N. We discover sev ...

SCIPOST FOUNDATION2023

De Novo Crystal Structure Determination from Machine Learned Chemical Shifts

David Lyndon Emsley, Manuel Cordova, Albert Hofstetter, Martins Balodis

Determination of the three-dimensional atomic-level structure of powdered solids is one of the key goals in current chemistry. Solid-state NMR chemical shifts can be used to solve this problem, but they are limited by the high computational cost associated ...

2022

Cubic, hexagonal and tetragonal FeGex phases (x = 1, 1.5, 2): Raman spectroscopy and magnetic properties

Anna Fontcuberta i Morral, Dirk Grundler, Nicolas Tappy, Mirjana Dimitrievska, Santhanu Panikar Ramanandan, Anna Kúkol'ová

There is currently an emerging drive towards computational materials design and fabrication of predicted novel materials. One of the keys to developing appropriate fabrication methods is determination of the composition and phase. Here we explore the FeGe ...

2021

Physics-enhanced machine learning with symmetry-adapted and long-range representations

Andrea Grisafi

Theoretical and computational approaches to the study of materials and molecules have, over the last few decades, progressed at an exponential rate. Yet, the possibility of producing numerical predictions that are on par with experimental measurements is t ...

EPFL2021

Electrochemical reconstruction of ZnO for selective reduction of CO2 to CO

Andreas Züttel, Wen Luo, Jie Zhang, Kun Zhao, Emanuele Moioli

Electrocatalytic conversion of CO2 to valuable chemicals is a highly promising route to close the carbon cycle. Herein, Zn catalysts derived from electrochemical reconstruction of ZnO materials are presented as efficient CO2-to-CO catalysts. We found that ...

2020

Rapid Structure Determination of Molecular Solids Using Chemical Shifts Directed by Unambiguous Prior Constraints

David Lyndon Emsley, Albert Hofstetter, Arthur César Pinon, Federico Maria Paruzzo, Martins Balodis

NMR-based crystallography approaches involving the combination of crystal structure prediction methods, ab initio calculated chemical shifts and solid-state NMR experiments are powerful methods for crystal structure determination of microcrystalline powder ...

2019

New Approaches to NMR Crystallography

Federico Maria Paruzzo

The first full protocol for nuclear magnetic resonance (NMR) crystallography (NMRX) using chemical shifts was developed a decade ago, and it combines experimental isotropic chemical shifts with crystal structure prediction (CSP) and with the calculation of ...

EPFL2019

Large-Scale Computational Screening of Molecular Organic Semiconductors Using Crystal Structure Prediction

Michele Ceriotti, Sandip De

Predictive computational methods have the potential to significantly accelerate the discovery of new materials with targeted properties by guiding the choice of candidate materials for synthesis. Recently, a planar pyrrole-based azaphenacene molecule (pyri ...

2018

Anharmonic and Quantum Fluctuations in Molecular Crystals: A First-Principles Study of the Stability of Paracetamol

Michele Ceriotti, Mariana Rossi Carvalho, Piero Gasparotto

Molecular crystals often exist in multiple competing polymorphs, showing significantly different physicochemical properties. Computational crystal structure prediction is key to interpret and guide the search for the most stable or useful form, a real chal ...

2016

Hg(II) coordination complexes containing the tris(2-pyridylmethyl) amine ligand: Synthesis, characterization and crystal structure analysis

Kurt Schenk, Farzaneh Fadaei Tirani

Two new Hg(II) coordination compounds containing the tris(2-pyridylmethyl)amine (TPA) ligand were synthesized by conventional and sonochemical methods, characterized by spectroscopic techniques (FT-IR and elemental analysis) and their X-ray crystallographi ...

Elsevier2016

Activation of G-protein-coupled receptors correlates with the formation of a continuous internal water pathway

Horst Arthur Vogel, Shuguang Yuan

Recent crystal structures of G-protein-coupled receptors (GPCRs) have revealed ordered internal water molecules, raising questions about the functional role of those waters for receptor activation that could not be answered by the static structures. Here, ...

Nature Publishing Group2014

Complete C-13 NMR Chemical Shifts Assignment for Cholesterol Crystals by Combined CP-MAS Spectral Editing and ab Initio GIPAW Calculations with Dispersion Forces

We report here the first fully oh initio determination of C-13 NMR spectra for several crystal structures of cholesterol, observed in various biomaterials. We combine Gauge-Including Projector Augmented Waves (GIPAW) calculations at relaxed structures, ful ...

2012

Synthesis of Room-Temperature Ionic Liquids with the Weakly Coordinating [Al(ORF)4]- Anion (RF=C(H)(CF3)2) and the Determination of Their Principal Physical Properties

Paul Joseph Dyson, Gabor Laurenczy, Safak Bulut

A large series of ionic liqs. (ILs) based on the weakly coordinating alkoxyaluminate [Al(hfip)4]- (hfip: hexafluoroisopropoxy) with classical as well as functionalized cations were prepd., and their principal phys. properties detd. M.ps. are between 0 ([C4 ...

2010

Ab initio structure solution by iterative phase-retrieval methods: performance tests on charge flipping and low-density elimination

Thomas Alois Weber

Comprehensive tests on the density-modification methods charge flipping [Oszlanyi & Suto (2004). Acta Cryst. A60, 134-141] and low-density elimination [Shiono & Woolfson (1992). Acta Cryst. A48, 451-456] for solving crystal structures are performed on simu ...

2010

SUPERFLIP– a computer program for the solution of crystal structures by charge flipping in arbitrary dimensions

Gervais Chapuis

SUPERFLIP is a computer program that can solve crystal structures from diffraction data using the recently developed charge-flipping algorithm. It can solve periodic structures, incommensurately modulated structures and quasicrystals from X-ray and neutron ...

2007

Phase diagram of pseudobinary Pb(Yb1/2Nb1/2)O-3-Pb(Sc1/2Nb1/2)O-3 ceramic solid solution

Nava Setter

Crystal structure and dielectric properties of (1-x)Pb(Yb1/2Nb1/2)O-3-xPb(Sc1/2Nb1/2)O-3 (PYN1-xPSNx) (0less than or equal toxless than or equal to0.60) solid solution have been studied, and its pseudobinary phase diagram has been determined. The low-tempe ...

2005