Second-Order Self-Consistent-Field Density-Matrix Renormalization Group
Yingjin Ma, Stefan Knecht, Sebastian Keller, Markus Reiher
We present a matrix-product state (MPS)-based quadratically convergent density-matrix renormalization group self-consistent-field (DMRG-SCF) approach. Following a proposal by Werner and Knowles (JCP 82, 5053, (1985)), our DMRG-SCF algorithm is based on...
A nonorthogonal state-interaction approach for matrix product state wave functions
Stefan Knecht, Sebastian Keller, Jochen Autschbach, Markus Reiher
We present a state-interaction approach for matrix product state (MPS) wave functions in a nonorthogonal molecular orbital basis. Our approach allows us to calculate...
Multi-reference perturbation theory with Cholesky decomposition for the density matrix renormalization group
Leon Freitag, Stefan Knecht, Celestino Angeli, Markus Reiher
We present a second-order N-electron valence state perturbation theory (NEVPT2) based on a density matrix renormalization group (DMRG) reference wave function that exploits a Cholesky decomposition of the two-electron repulsion integrals (CD-DMRG-NEVPT2). With a parameter-free multireference perturbation theory approach at hand, the latter allows us...
The Delicate Balance of Static and Dynamic Electron Correlation
Christopher J. Stein, Vera von Burg, Markus Reiher
Multi-configurational approaches yield universal wave function parameterizations that can qualitatively well describe electronic structures along reaction pathways. For quantitative results, multi-reference perturbation theory is required to capture dynamic...
Elucidating Reaction Mechanisms on Quantum Computers
Markus Reiher, Nathan Wiebe, Krysta M Svore, Dave Wecker, Matthias Troyer
We show how a quantum computer can be employed to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment...
Molecular propensity as a driver for explorative reactivity studies
Alain C. Vaucher, Markus Reiher
Quantum chemical studies of reactivity involve calculations on a large number of molecular structures and comparison of their energies. Already the set-up of these calculations limits the scope of the results that one will obtain,...