10 papers
Second-Derivative-Corrected FANPT for Robust Continuation of Nonlinear Wavefunction Equations
Rugwed Lokhande, Krisztina Zsigmond, Paul W. Ayers +1
We present a second-derivative-corrected extension of the Flexible Ansatz for N-body Perturbation Theory (FANPT) for solving nonlinear Flexible Ansatz for N-body Configuration Inte…
Fanpy 2.0: Wavefunction Implementation and Analysis Tools for Flexible Ansatz Design
Krisztina Zsigmond, Rugwed Lokhande, Carlos E. V. de Moura +6
Fanpy is a Python library for developing new wavefunction methods. It enables users to quickly convert mathematical expressions into working code through a modular design based on…
Baker-Campbell-Hausdorff expansion in creation-only coupled cluster
Ramón Alain Miranda-Quintana
We study the properties of the exponential ansatz formed by strings of creation operators. We discuss the conditions under which we can recover a structure similar to traditional c…
A new family of seniority-restricted coupled cluster methods
Ramón Alain Miranda-Quintana, Rugwed Lokhande, Carlos E. V. de Moura +2
We introduce a novel class of coupled cluster (CC) methods that leverage the seniority concept to enhance efficiency and accuracy in electronic structure calculations. While existi…
Coupled Cluster-Inspired Geminal Wavefunctions
Pratiksha B. Gaikwad, Taewon D. Kim, M. Richer +5
Electron pairs have an illustrious history in chemistry, from powerful concepts to understanding structural stability and reactive changes, to the promise of serving as building bl…
Flexible Ansatz for N-body Perturbation Theory
Ramón Alain Miranda-Quintana, Taewon D. Kim, Rugwed A. Lokhande +4
We propose a new Perturbation Theory framework that can be used to help with the projective solution of the Schrödinger equation for arbitrary wavefunctions. This Flexible Ansatz f…
Inductive Proof of Borchardt's Theorem
Andy A. Chavez, Alec P. Adam, Paul W. Ayers +1
We provide an inductive proof of Borchardt's theorem for calculating the permanent of a Cauchy matrix via the determinants of auxiliary matrices. This result has implications for a…
A kinetic perspective of charge transfer reactions: the downfall of hard/soft acid/base interactions
Ramon Alain Miranda Quintana
We show how to incorporate the possibility of kinetic control in the conceptual Density Functional Theory formalism. This allow us to prove that the hard/soft acid/base principle w…
Fanpy: A Python Library for Prototyping Multideterminant Methods in Ab Initio Quantum Chemistry
Taewon David Kim, Michael Richer, Gabriela Sánchez-Díaz +4
Fanpy is a free and open-source Python library for developing and testing multideterminant wavefunctions and related ab initio methods in electronic structure theory. The main use…
Flexible ansatz for N-body Configuration Interaction
Taewon David Kim, Ramón Alain Miranda-Quintana, Michael Richer +1
We present a Flexible Ansatz for N-body Configuration Interaction (FANCI) that includes any multideterminant wavefunction. This ansatz is a generalization of the Configuration Inte…