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Related papers: Accurate ab initio spin densities

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We present an implementation of the relativistic quantum-chemical density matrix renormalization group (DMRG) approach based on a matrix-product formalism. Our approach allows us to optimize matrix product state (MPS) wave functions…

Chemical Physics · Physics 2017-10-24 Stefano Battaglia , Sebastian Keller , Stefan Knecht

We extend the spin-adapted density matrix renormalization group (DMRG) algorithm of McCulloch and Gulacsi [Europhys. Lett.57, 852 (2002)] to quantum chemical Hamiltonians. This involves two key modifications to the non-spin-adapted DMRG…

Chemical Physics · Physics 2014-08-22 Sandeep Sharma , Garnet Kin-Lic Chan

We present an efficient implementation of the Density Matrix Renormalization Group (DMRG) algorithm that includes an optimal ordering of the proton and neutron orbitals and an efficient expansion of the active space utilizing various…

Nuclear Theory · Physics 2015-11-18 Ö. Legeza , L. Veis , A. Poves , J. Dukelsky

A new density matrix renormalisation group (DMRG) approach is presented for quantum systems of two spatial dimensions. In particular, it is shown that it is possible to create a multi-chain-type 2D DMRG approach which utilises previously…

Strongly Correlated Electrons · Physics 2009-11-10 Damian J. J. Farnell

We study the one-dimensional $S=1/2$ Heisenberg model with a uniform and a staggered magnetic fields, using the dynamical density-matrix renormalization group (DDMRG) technique. The DDMRG enables us to investigate the dynamical properties…

Strongly Correlated Electrons · Physics 2007-10-19 S. Nishimoto , M. Arikawa

We present an efficient stochastic algorithm for the recently introduced perturbative density matrix renormalization group (p-DMRG) method for large active spaces. The stochastic implementation bypasses the computational bottleneck involved…

Chemical Physics · Physics 2018-08-01 Sheng Guo , Zhendong Li , Garnet Kin-Lic Chan

The density-matrix renormalization group (DMRG) method, which can deal with a large active space composed of tens of orbitals, is nowadays widely used as an efficient addition to traditional complete active space (CAS)-based approaches. In…

Strongly Correlated Electrons · Physics 2016-11-06 Yingjin Ma , Jing Wen , Haibo Ma

We propose a simple modification of the density matrix renormalization group (DMRG) method in order to tackle strongly disordered quantum spin chains. Our proposal, akin to the idea of the adaptive time-dependent DMRG, enables us to reach…

Strongly Correlated Electrons · Physics 2018-11-14 J. C. Xavier , J. A. Hoyos , E. Miranda

It is well-known that not only the orbital ordering but also the choice of the orbitals themselves as the basis may significantly influence the computational efficiency of density-matrix renormalization group (DMRG) calculations. In this…

Strongly Correlated Electrons · Physics 2013-06-14 Yingjin Ma , Haibo Ma

For quantum spin models defined on a two-dimensional lattice, we look for the best numbering of the lattice sites (a layout) that, at fixed bond dimension and other parameters of the density matrix renormalization group (DMRG) algorithm,…

Strongly Correlated Electrons · Physics 2026-03-09 A. Scardicchio

We present a procedure to construct a configuration-interaction expansion containing arbitrary excitations from an underlying full-configuration-interaction-type wave function defined for a very large active space. Our procedure is based on…

Chemical Physics · Physics 2011-06-14 Katharina Boguslawski , Konrad H. Marti , Markus Reiher

The spin 1/2 XXZ chain in a random magnetic field pointing in the Z direction is numerically studied using the Density Matrix Renormalization Group (DMRG) method. The phase diagram as a function of the anisotropy of the XXZ Hamiltonian and…

Strongly Correlated Electrons · Physics 2009-11-07 Laura Urba , Anders Rosengren

Understanding the intricate properties of one-dimensional quantum systems coupled to multiple reservoirs poses a challenge to both analytical approaches and simulation techniques. Fortunately, density matrix renormalization group-based…

Quantum Physics · Physics 2021-07-15 Heitor P. Casagrande , Dario Poletti , Gabriel T. Landi

The density matrix renormalization group (DMRG) method generates the low-energy states of linear systems of $N$ sites with a few degrees of freedom at each site by starting with a small system and adding sites step by step while keeping…

Strongly Correlated Electrons · Physics 2016-10-05 Manoranjan Kumar , Dayasindhu Dey , Aslam Parvej , S. Ramasesha , Zoltán G. Soos

The density matrix renormalization group (DMRG) has become an indispensable numerical tool to find exact eigenstates of finite-size quantum systems with strong correlation. In the fields of condensed matter, nuclear structure and molecular…

Strongly Correlated Electrons · Physics 2014-04-21 Sebastian Wouters , Ward Poelmans , Paul W. Ayers , Dimitri Van Neck

We present a numerical implementation of the density matrix renormalization group (DMRG) using the discrete variable representation (DVR) basis set. One main advantage of using the local DVR basis sets is that the computations of…

Quantum Physics · Physics 2024-11-13 Bing Gu

During the past 15 years, the density matrix renormalization group (DMRG) has become increasingly important for ab initio quantum chemistry. Its underlying wavefunction ansatz, the matrix product state (MPS), is a low-rank decomposition of…

Chemical Physics · Physics 2014-09-25 Sebastian Wouters , Dimitri Van Neck

We introduce a hybrid approach to applying the density matrix renormalization group (DMRG) to continuous systems, combining a grid approximation along one direction with a finite Gaussian basis set along the remaining two directions. This…

Chemical Physics · Physics 2017-08-02 E. Miles Stoudenmire , Steven R. White

We propose a new approach to implement the density matrix renormalization group (DMRG) in two dimensions. With this approach the initial blocks of a L by L lattice are built up directly from the matrix elements of a (L-1) by L-1) lattice…

Strongly Correlated Electrons · Physics 2009-11-07 Tao Xiang , Jizhong Lou , Zhaobin Su

An efficient density matrix renormalization group (DMRG) algorithm is presented for the Bethe lattice with connectivity $Z = 3$ and antiferromagnetic exchange between nearest neighbor spins $s= 1/2$ or 1 sites in successive generations $g$.…

Strongly Correlated Electrons · Physics 2015-06-03 Manoranjan Kumar , S. Ramasesha , Zoltan G. Soos
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