English
Related papers

Related papers: Orbital Optimization in the Active Space Decomposi…

200 papers

We develop the theory of Energy Conserving Descent (ECD) and introduce ECDSep, a gradient-based optimization algorithm able to tackle convex and non-convex optimization problems. The method is based on the novel ECD framework of…

Machine Learning · Computer Science 2023-06-02 G. Bruno De Luca , Alice Gatti , Eva Silverstein

In this work, we investigate the possibility of improving multireference-driven coupled cluster (CC) approaches with an algorithm that iteratively combines complete active space (CAS) calculations with tailored CC and externally corrected…

Chemical Physics · Physics 2025-03-06 Robin Feldmann , Max Mörchen , Jakub Lang , Michał Lesiuk , Markus Reiher

In this paper, we propose a computationally efficient iterative algorithm for proper orthogonal decomposition (POD) using random sampling based techniques. In this algorithm, additional rows and columns are sampled and a merging technique…

Numerical Analysis · Mathematics 2020-11-23 Charumathi V , M. Ramakrishna , Vinita Vasudevan

In this paper, we propose a computationally efficient iterative algorithm for proper orthogonal decomposition (POD) using random sampling based techniques. In this algorithm, additional rows and columns are sampled and a merging technique…

Numerical Analysis · Computer Science 2021-07-07 V. Charumathi , M. Ramakrishna , Vinita Vasudevan

The anisotropic two-orbital Hubbard model is investigated at low temperatures using high-precision quantum Monte Carlo (QMC) simulations within dynamical mean-field theory (DMFT). We demonstrate that two distinct orbital-selective Mott…

Strongly Correlated Electrons · Physics 2015-06-25 N. Blümer , C. Knecht , K. Pozgajcic , P. G. J. van Dongen

The exchange-correlation energy in Kohn-Sham density functional theory is expressed as a functional of the electronic density and the Kohn-Sham orbitals. An alternative to Kohn-Sham theory is to express the energy as a functional of the…

Computational Physics · Physics 2009-10-31 S. Goedecker , C. Umrigar

Theories of self-organized active fluid surfaces have emerged as an important class of minimal models for the shape dynamics of biological membranes, cells and tissues. However, due to their inherent geometric nonlinearities and the absence…

Soft Condensed Matter · Physics 2025-07-16 Da Gao , Huayang Sun , Rui Ma , Alexander Mietke

We apply a number of atomic decomposition schemes across the standard QM7 dataset -- a small model set of organic molecules at equilibrium geometry -- to inspect the possible emergence of trends among contributions to atomization energies…

Chemical Physics · Physics 2023-04-19 Frederik Ø. Kjeldal , Janus J. Eriksen

Recent high resolution Compton scattering experiments clearly reveal that there are fundamental limitations to the conventional local density approximation (LDA) based description of the ground state electron momentum density (EMD) in…

Strongly Correlated Electrons · Physics 2007-10-11 B. Barbiellini , A. Bansil

A family of deformed AdS$_5$-Schwarzschild black branes is here derived, employing the membrane paradigm of AdS/CFT. The solution of the Einstein-Hilbert action, with the Gibbons-Hawking term and a counter-term that eliminates eventual…

High Energy Physics - Theory · Physics 2020-06-15 A. J. Ferreira-Martins , P. Meert , R. da Rocha

Spectral decomposition of linear operators plays a central role in many areas of machine learning and scientific computing. Recent work has explored training neural networks to approximate eigenfunctions of such operators, enabling scalable…

Machine Learning · Computer Science 2025-10-28 J. Jon Ryu , Samuel Zhou , Gregory W. Wornell

We analyze the two-orbital Hubbard model by means of the Composite Operator Method with the aim at studying the phenomenon of orbital selective Mott transition (OSMT). The model contains an interorbital interaction $U'$, in addition to the…

Strongly Correlated Electrons · Physics 2015-05-13 Adolfo Avella , Ferdinando Mancini , Satoru Odashima , Giovanni Scelza

Spatially localized one-electron orbitals, orthogonal and nonorthogonal, are widely used in electronic structure theory to describe chemical bonding and speed up calculations. In order to avoid linear dependencies of localized orbitals, the…

Chemical Physics · Physics 2020-03-04 Ziling Luo , Rustam Z. Khaliullin

We have compared the performance of Grimme style DH/DSD and Zhang-Xu-Goddard type xDH/xDSD forms for double hybrids. In the DH and DSD forms, KS orbitals with elevated HF exchange and damped DFT correlation are used, while in the xDH and…

Chemical Physics · Physics 2015-11-12 Manoj Kumar Kesharwani , Sebastian Kozuch , Jan M. L. Martin

We introduce a theoretical framework for computaions of anisotropic multipolar exchange interactions found in many spin--orbit coupled magnetic systems and propose a method to extract these coupling constants using a density functional…

Strongly Correlated Electrons · Physics 2014-08-01 Shu-Ting Pi , Ravindra Nanguneri , Sergey Savrasov

We present a first-principles atomistic thermodynamics framework to describe the structure, composition and segregation profile of an alloy surface in contact with a (reactive) environment. The method is illustrated with the application to…

Materials Science · Physics 2009-11-13 John Kitchin , Karsten Reuter , Matthias Scheffler

The atomic third-order open-shell many-body perturbation theory is developed. Special attention is paid to the generation and algebraic analysis of terms of the wave operator and the effective Hamiltonian as well. Making use of…

Atomic Physics · Physics 2015-05-19 R. Jursenas , G. Merkelis

Fractionalization of an electronic quasiparticle into spin, charge and orbital parts is a fundamental and characteristic property of interacting electrons in one dimension. However, real materials are never strictly one-dimensional and the…

Excited electronic states of molecules and solids play a fundamental role in fields such as catalysis and electronics. In electronic structure calculations, excited states typically correspond to saddle points on the surface described by…

The imposition of a constraint between the metric tensor elements in both three- and four-dimensional, rotating AdS space-times is shown to reduce the number of independent equations of motion and to result in new families of solutions to…

General Relativity and Quantum Cosmology · Physics 2019-06-19 Benjamin Harms