# Challenges in large scale quantum mechanical calculations

@article{Ratcliff2016ChallengesIL, title={Challenges in large scale quantum mechanical calculations}, author={Laura E. Ratcliff and Stephan Mohr and Georg Huhs and Thierry Deutsch and Michel Masella and Luigi Genovese}, journal={Wiley Interdisciplinary Reviews: Computational Molecular Science}, year={2016}, volume={7} }

During the past decades, quantum mechanical methods have undergone an amazing transition from pioneering investigations of experts into a wide range of practical applications, made by a vast community of researchers. First principles calculations of systems containing up to a few hundred atoms have become a standard in many branches of science. The sizes of the systems which can be simulated have increased even further during recent years, and quantum‐mechanical calculations of systems up to…

## 75 Citations

Density functional theory calculations of large systems: Interplay between fragments, observables, and computational complexity

- PhysicsWIREs Computational Molecular Science
- 2021

In the past decade, developments of computational technology around density functional theory (DFT) calculations have considerably increased the system sizes which can be practically simulated. The…

Linear scaling DFT calculations for large Tungsten systems using an optimized local basis

- Physics
- 2017

Multireference Approaches for Excited States of Molecules.

- Chemistry, PhysicsChemical reviews
- 2018

The purpose of this review is to provide an overview of the most important facts about the different theoretical approaches available and to present by means of a collection of characteristic examples useful information, which can guide the reader in performing their own applications.

Complexity Reduction in Density Functional Theory Calculations of Large Systems: System Partitioning and Fragment Embedding.

- Computer ScienceJournal of chemical theory and computation
- 2020

A systematic complexity reduction methodology which can break down large systems into their constituent fragments, and quantify inter-fragment interactions is presented.

Pseudo-fragment approach for extended systems derived from linear-scaling DFT.

- Computer ScienceJournal of physics. Condensed matter : an Institute of Physics journal
- 2019

The method enables one to identify the regions of an extended system which require dedicated optimization of the Kohn-Sham degrees of freedom, and provides the user with a reliable estimation of the errors-if any-induced by the locality of the approach.

Cost-effective composite methods for large-scale solid-state calculations.

- Materials ScienceFaraday discussions
- 2020

The applicability and scaling of the new sol-3c DFT methods to molecules and crystals composed of light-elements, such as small proteins and model DNA-helices are analyzed and the calculation of the electronic structure of large to very large porous systems, Such as metal-organic frameworks and inorganic nanoparticles are discussed.

Quantum Mechanically Derived Biomolecular Force Fields

- Chemistry, Physics
- 2019

Molecular mechanics force fields are used to understand and predict a wide range of biological phenomena. However, current biomolecular force fields assume that parameters must be fit to the…

Toward Efficient GW Calculations Using Numerical Atomic Orbitals: Benchmarking and Application to Molecular Dynamics Simulations.

- PhysicsJournal of chemical theory and computation
- 2019

An implementation of the GW approximation using numerical atomic orbitals and a pseudopotential treatment of core electrons and the computed thermal line widths indicate approximately twice as large electron-phonon couplings with GW than with standard DFT-GGA calculations.

Complexity Reduction in Large Quantum Systems: Fragment Identification and Population Analysis via a Local Optimized Minimal Basis.

- Computer ScienceJournal of chemical theory and computation
- 2017

This work presents a quantitative method to identify and assess the partitioning of a large quantum-mechanical system into fragments and shows that the use of a minimal set of in situ-optimized basis functions allows at the same time a proper fragment definition and an accurate description of the electronic structure.

On the achievement of high fidelity and scalability for large‐scale diagonalizations in grid‐based DFT simulations

- Computer Science
- 2018

This work proposes a numerically robust method that enables scalable diagonalizations of large DFT Hamiltonian matrices, particularly with thousands of computing CPUs (cores) that are usual these days in terms of sizes of HPC resources.

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