1.2k citations · 4k across the 48 of their papers we have counts for
50 papers
Learning the Kohn-Sham map with neural operators for quasi-linear scaling density functional theory
Danish Khan, Maurice D. Hanisch, Nikolai Argatoff +3
Kohn--Sham density functional theory (DFT) underpins electronic-structure simulations, but repeated orbital diagonalizations lead to cubic scaling, restricting quantum calculations…
Size Extensive Auxiliary-Field Quantum Monte Carlo with Perturbative Coupled Cluster Trial Wavefunction
Yichi Zhang, Ankit Mahajan, Yann Damour +1
In this work, we develop a size extensive Auxiliary-Field Quantum Monte Carlo (AFQMC) approach that scales as for local energy evaluation by treating the Coupled Cluster S…
Can phaseless auxiliary-field quantum Monte Carlo with broken symmetry trials describe iron-sulfur clusters?
Eirik F. Kjønstad, Huanchen Zhai, James Shee +2
Phaseless auxiliary-field quantum Monte Carlo (AFQMC) has in several cases been found to perform well on strongly correlated systems. Here, we benchmark the method for three iron-s…
Chemistry Beyond the Scale of Exact Diagonalization on a Quantum-Centric Supercomputer
Javier Robledo-Moreno, Mario Motta, Holger Haas +14
A universal quantum computer can simulate diverse quantum systems, with electronic structure for chemistry offering challenging problems for practical use cases around the hundred-…
Convergence Analysis of the Stochastic Resolution of Identity: Comparing Hutchinson to Hutch++ for the Second-Order Green's Function
Leopoldo Mejía, Sandeep Sharma, Roi Baer +2
Stochastic orbital techniques offer reduced computational scaling and memory requirements to describe ground and excited states at the cost of introducing controlled statistical er…
Toward linear scaling auxiliary field quantum Monte Carlo with local natural orbitals
Jo S. Kurian, Hong-Zhou Ye, Ankit Mahajan +2
We develop a local correlation variant of auxiliary field quantum Monte Carlo (AFQMC) that is based on local natural orbitals (LNO-AFQMC). In LNO-AFQMC, independent AFQMC calculati…
Response properties in phaseless auxiliary field quantum Monte Carlo
Ankit Mahajan, Jo S. Kurian, Joonho Lee +2
We present a method for calculating first-order response properties in phaseless auxiliary field quantum Monte Carlo (AFQMC) through the application of automatic differentiation (A…
Relativistic semistochastic heat-bath configuration interaction
Xubo Wang, Sandeep Sharma
In this work we present the extension of semistochastic heat-bath configuration interaction (SHCI) to work with any two-component and four-component Hamiltonian. Vertical detachmen…
Fast exchange with Gaussian basis set using robust pseudospectral method
Sandeep Sharma, Alec F. White, Gregory Beylkin
In this article we present an algorithm to efficiently evaluate the exchange matrix in periodic systems when Gaussian basis set with pseudopotentials are used. The usual algorithm…
Selected configuration interaction wave functions in phaseless auxiliary field quantum Monte Carlo
Ankit Mahajan, Joonho Lee, Sandeep Sharma
We present efficient algorithms for using selected configuration interaction (sCI) trial wave functions in phaseless auxiliary field quantum Monte Carlo (ph-AFQMC). These advanceme…
Near-Exact Nuclear Gradients of Complete Active Space Self-Consistent Field Wave Functions
James E. T. Smith, Joonho Lee, Sandeep Sharma
In this paper, we study the nuclear gradients of heat bath configuration interaction self-consistent field (HCISCF) wave functions and use them to optimize molecular geometries for…
Highly accurate ab-initio thermochemistry via real-space quantum Monte Carlo: Benzene
Iliya Sabzevari, Sandeep Sharma
Real-space quantum Monte Carlo is used to calculate the total atomization energy of benzene. In contrast to orbital-space methods common in quantum chemistry, real-space methods al…
A fast algorithm for computing the Boys function
Gregory Beylkin, Sandeep Sharma
We present a new fast algorithm for computing the Boys function using a nonlinear approximation of the integrand via exponentials. The resulting algorithms evaluate the Boys functi…
Taming the sign problem in auxiliary field quantum Monte Carlo using accurate trial wave functions
Ankit Mahajan, Sandeep Sharma
We explore different ways of incorporating accurate trial wave functions into free projection auxiliary field quantum Monte Carlo (fp-AFQMC). Trial states employed include coupled…
Externally corrected CCSD with renormalized perturbative triples (R-ecCCSD(T)) and density matrix renormalization group and selected configuration interaction external sources
Seunghoon Lee, Huanchen Zhai, Sandeep Sharma +2
We investigate the renormalized perturbative triples correction together with the externally corrected coupled-cluster singles and doubles (ecCCSD) method. We take the density matr…
Efficient evaluation of two-center Gaussian integrals in periodic systems
Sandeep Sharma, Gregory Beylkin
By using Poisson's summation formula, we calculate periodic integrals over Gaussian basis functions by partitioning the lattice summations between the real and reciprocal space, wh…
Efficient local energy evaluation for multi-Slater wave functions in orbital space quantum Monte Carlo
Ankit Mahajan, Sandeep Sharma
Recent developments in selected configuration interaction methods have led to increased interest in using multi-Slater trial wave functions in various quantum Monte Carlo (QMC) met…
The Ground State Electronic Energy of Benzene
Janus J. Eriksen, Tyler A. Anderson, J. Emiliano Deustua +21
We report on the findings of a blind challenge devoted to determining the frozen-core, full configuration interaction (FCI) ground state energy of the benzene molecule in a standar…
Efficient multireference perturbation theory without high-order reduced density matrices
Nick S. Blunt, Ankit Mahajan, Sandeep Sharma
We present a stochastic approach to perform strongly contracted n-electron valence state perturbation theory (SC-NEVPT), which only requires one- and two-body reduced density matri…
Recent developments in the PySCF program package
Qiming Sun, Xing Zhang, Samragni Banerjee +46
PYSCF is a Python-based general-purpose electronic structure platform that both supports first-principles simulations of molecules and solids, as well as accelerates the developmen…
Direct comparison of many-body methods for realistic electronic Hamiltonians
Kiel T. Williams, Yuan Yao, Jia Li +22
A large collaboration carefully benchmarks 20 first principles many-body electronic structure methods on a test set of 7 transition metal atoms, and their ions and monoxides. Good…
Accurate many-body electronic structure near the basis set limit: application to the chromium dimer
Junhao Li, Yuan Yao, Adam A. Holmes +4
We describe a method for computing near-exact energies for correlated systems with large Hilbert spaces. The method efficiently identifies the most important basis states (Slater d…
Multireference configuration interaction and perturbation theory without reduced density matrices
Ankit Mahajan, Nick S. Blunt, Iliya Sabzevari +1
The computationally expensive evaluation and storage of high-rank reduced density matrices (RDMs) has been the bottleneck in the calculation of dynamic correlation for multireferen…
An accelerated linear method for optimizing non-linear wavefunctions in variational Monte Carlo
Iliya Sabzevari, Ankit Mahajan, Sandeep Sharma
Although the linear method is one of the most robust algorithms for optimizing non-linearly parametrized wavefunctions in variational Monte Carlo, it suffers from a memory bottlene…