English
Related papers

Related papers: Iterative Configuration Interaction with Selection

200 papers

We consider gradient descent and quasi-Newton algorithms to optimize the full configuration interaction (FCI) ground state wavefunction starting from an arbitrary reference state $|0 \rangle$. We show that the energies obtained along the…

Chemical Physics · Physics 2021-02-03 Carlos A. Jiménez-Hoyos

The tailored coupled cluster (TCC) approach is a promising ansatz that preserves the simplicity of single-reference coupled cluster theory, while incorporating a multi-reference wave function through amplitudes obtained from a preceding…

Chemical Physics · Physics 2021-01-07 Maximilian Mörchen , Leon Freitag , Markus Reiher

Selected configuration interaction (SCI) methods have emerged as state-of-the-art methodologies for achieving high accuracy and generating benchmark reference data for ground and excited states in small molecular systems. However, their…

Chemical Physics · Physics 2024-06-13 Hugh G. A. Burton , Pierre-François Loos

The computationally expensive evaluation and storage of high-rank reduced density matrices (RDMs) has been the bottleneck in the calculation of dynamic correlation for multireference wave functions in large active spaces. We present a…

Chemical Physics · Physics 2020-01-08 Ankit Mahajan , Nick S. Blunt , Iliya Sabzevari , Sandeep Sharma

We have combined our adaptive configuration interaction (ACI) [J.B. Schriber and F.A. Evangelista, J. Chem. Phys. 144, 161106 (2016)] with a density-fitted implementation of the second-order perturbative multireference driven similarity…

Chemical Physics · Physics 2018-08-29 Jeffrey B. Schriber , Kevin P. Hannon , Francesco A. Evangelista

Transformation-robustness is an important feature for machine learning models that perform image classification. Many methods aim to bestow this property to models by the use of data augmentation strategies, while more formal guarantees are…

Computer Vision and Pattern Recognition · Computer Science 2022-10-21 Sai Raam Venkataraman , S. Balasubramanian , R. Raghunatha Sarma

Methods for correcting residual energy errors of configuration interaction (CI) calculations of molecules and other electronic systems are discussed based on the assumption that the energy defect can be mapped onto atomic regions. The…

Chemical Physics · Physics 2022-10-05 Jerry L. Whitten

Reconfigurable intelligent surfaces (RISs) are a promising solution to improve the coverage of cellular networks, thanks to their ability to steer impinging signals in desired directions. However, they introduce an overhead in the…

Signal Processing · Electrical Eng. & Systems 2024-03-21 Anna V. Guglielmi , Stefano Tomasin

A good clustering can help a data analyst to explore and understand a data set, but what constitutes a good clustering may depend on domain-specific and application-specific criteria. These criteria can be difficult to formalize, even when…

Machine Learning · Statistics 2016-06-09 Akash Srivastava , James Zou , Charles Sutton

Invariant Coordinate Selection (ICS) is a multivariate technique that relies on the simultaneous diagonalization of two scatter matrices. It serves various purposes, including its use as a dimension reduction tool prior to clustering or…

Methodology · Statistics 2025-12-18 Colombe Becquart , Aurore Archimbaud , Anne Ruiz-Gazen , Luka Prilć , Klaus Nordhausen

First-principles based crystal structure prediction (CSP) methods have revealed an essential tool for the discovery of new materials. However, in solids close to displacive phase transitions, which are common in ferroelectrics,…

Materials Science · Physics 2026-04-17 Hao Gao , Yue-Wen Fang , Ion Errea

Reconfigurable Intelligent Surfaces (RISs) are becoming one of the fundamental building blocks of next-generation wireless communication systems. To that end, RIS phase configuration optimization is an important issue, where finding the…

Signal Processing · Electrical Eng. & Systems 2023-08-07 Samed Keşir , M. Yaser Yağan , İbrahim Hökelek , Ali Emre Pusane , Ali Görçin

Non-orthogonal configuration interaction (NOCI) is a generalization of the standard orthogonal configuration interaction (CI) method and offers a highly flexible framework for describing ground and excited electronic states. However, this…

Chemical Physics · Physics 2024-12-24 Daniel Graf , Alex J. W. Thom

The goal of data selection is to capture the most structural information from a set of data. This paper presents a fast and accurate data selection method, in which the selected samples are optimized to span the subspace of all data. We…

Computer Vision and Pattern Recognition · Computer Science 2018-11-30 Mohsen Joneidi , Alireza Zaeemzadeh , Nazanin Rahnavard , Mubarak Shah

An externally corrected coupled cluster (CC) method, where an adaptive configuration interaction (ACI) wave function provides the external cluster amplitudes, named ACI-CC, is presented. By exploiting the connection between configuration…

Chemical Physics · Physics 2023-09-27 Gustavo J. R. Aroeira , Madeline M. Davis , Justin M. Turney , Henry F. Schaefer

Selective configuration interaction methods approximate correlated molecular ground- and excited states by considering only the most relevant Slater determinants in the expansion. While a recently proposed neural-network-assisted approach…

Accurate solution of the many-electron problem including correlations remains intractable except for few-electron systems. Describing interacting electrons as a superposition of independent electron configurations results in an apparent…

Computational Physics · Physics 2024-02-20 J. C. Greer

In this work, we develop a mathematical framework for a Selected Configuration Interaction (SCI) algorithm within a bi-orthogonal basis for transcorrelated (TC) calculations. The bi-orthogonal basis used here serves as the equivalent of the…

Chemical Physics · Physics 2023-06-22 Abdallah Ammar , Anthony Scemama , Emmanuel Giner

Previous methods solve feature matching and pose estimation using a two-stage process by first finding matches and then estimating the pose. As they ignore the geometric relationships between the two tasks, they focus on either improving…

Computer Vision and Pattern Recognition · Computer Science 2023-06-13 Fei Xue , Ignas Budvytis , Roberto Cipolla

The interplay between advances in stochastic and deterministic algorithms has recently led to development of interesting new selected configuration interaction (SCI) methods for solving the many body Schr\"{o}dinger equation. The…

Strongly Correlated Electrons · Physics 2018-08-08 Norm M. Tubman , Daniel S. Levine , Diptarka Hait , Martin Head-Gordon , K. Birgitta Whaley