Toward an automated analysis of exchange pathways in spin‐coupled systems

Steenbock, Torben; Herrmann, Carmen

doi:10.1002/jcc.25081

Cited by 12 publications

(17 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To analyze such through-bond vs through-bond contributions to exchange spin coupling, we have introduced a local decomposition of Heisenberg exchange coupling constants J (see Figure 6) based on an approach formulated in terms of Green's functions, 125,126 which distributes J onto the atoms of the molecules such that…”

Section: T E T E ( ) ( )mentioning

confidence: 99%

Electronic Communication as a Transferable Property of Molecular Bridges?

Herrmann

2019

J. Phys. Chem. A

Self Cite

View full text Add to dashboard Cite

Electronic communication through molecular bridges is important for different types of experiments, such as single-molecule conductance, electron transfer, superexchange spin coupling, and intramolecular singlet fission. In many instances, the chemical structure of the bridge determines how the two parts it is connecting communicate, and does so in ways that are transferable between these different manifestations (for example, high conductance often correlates with strong antiferromagnetic spin coupling, and low conductance due to destructive quantum interference correlates with ferromagnetic coupling). Defining electronic communication as a transferable property of the bridge can help transfer knowledge between these different areas of research. Examples and limits of such transferability are discussed here, along with some possible directions for future research, such as employing spin-coupled and mixed-valence systems as structurally wellcontrolled proxies for understanding molecular conductance and for validating first-principles theoretical methodologies, building conceptual understanding for the growing experimental work on intramolecular singlet fission, and developing measures for the transferability of electronic communication as a bridge property.

show abstract

Section: T E T E ( ) ( )mentioning

confidence: 99%

Electronic Communication as a Transferable Property of Molecular Bridges?

Herrmann

2019

J. Phys. Chem. A

Self Cite

View full text Add to dashboard Cite

show abstract

“…Other efforts in this direction are based on a Green's-function approach that also allows a fragment-based analysis. 50,51 Herein, we show how orbital entanglement measures can be connected to the magnetic topology of an exchange-coupled system represented by a multiconfigurational wave function, and demonstrate how changes in magnetic pathways due to chemical modifications in homologous complexes can be revealed and quantitatively analyzed. We note that for a numerically accurate reproduction of the exchange coupling constant itself, subsequent perturbation theory treatment as described earlier is needed to recover dynamical correlation, but the predicted coupling topology will not be affected by this.…”

mentioning

confidence: 98%

“…Ab initio calculations on magnetically coupled systems have been carried out with difference-dedicated configuration interaction (DDCI) and complete active space methods (CASSCF/CASPT2) among others, including an analysis of the underlying physics. − With the impending facile accessibility of multiconfigurational descriptions for many oligonuclear systems with DMRG, − analytical tools are needed that connect the quantum-chemical description to established interpretations and chemical concepts. Other efforts in this direction are based on a Green’s-function approach that also allows a fragment-based analysis. , …”

mentioning

confidence: 99%

Orbital Entanglement Analysis of Exchange-Coupled Systems

Stein

Pantazis

Krewald

2019

J. Phys. Chem. Lett.

View full text Add to dashboard Cite

A new tool for the interpretation of multiconfigurational wave functions representing the spin states of exchangecoupled transition metal complexes is introduced. Based on orbital entanglement measures, herein derived from multiconfigurational density matrix renormalization group calculations, the complexity of the wave function is reduced, thus facilitating a connection with established concepts for the interpretation of magnetically coupled systems. We show that the entanglement of localized orbitals with a small basis set is a good representation of the magnetic coupling topology and that it is sensitive to chemical changes in homologous complexes. Furthermore, we introduce a measure for the magnetic relevance of orbitals in the active subspace and a concept for the quantitative comparison of different chemical species. The approach presented here will be easily applicable to higher nuclearity clusters, providing a direct insight into all states of the Heisenberg spin ladder for systems previously accessible only by singleconfigurational methods.

show abstract

“…Nanoscopic systems in which spin coupling can be controlled by laser pulses [11,12] have potential applications in spin-only information transfer, storage [11,13], and quantum information processing [14][15][16]. While many studies have contributed to the understanding of spin coupling in the ground state, both theoretically [17][18][19] and experimentally [20,21], little is known on spin coupling in optically excited states [10].…”

Section: Introductionmentioning

confidence: 99%

Exchange Spin Coupling in Optically Excited States

Steenbock

Rybakowski

Benner

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

In optically excited states in molecules and materials, coupling between local electron spins plays an important role for their photoemission properties and is interesting for potential applications in quantum information processing. Recently, it was experimentally demonstrated that the photogenerated local spins in donor–acceptor metal complexes can interact with the spin of an attached radical, resulting in a spin-coupling dependent mixing of excited doublet states, which controls the local spin density distributions on donor, acceptor, and radical subunits in optically excited states. In this work, we propose an energy-difference scheme to evaluate spin coupling in optically excited states, using unrestricted and spin-flip simplified time-dependent density functional theory (sTDDFT). We apply it to three platinum complexes which have been studied experimentally to validate our methodology. We find that all computed coupling constants are in excellent agreement with the experimental data. In addition, we show that the spin coupling between donor and acceptor in the optically excited state can be fine-tuned by replacing platinum with palladium and zinc in the structure. Besides the two previously discussed excited doublet states (one bright and one dark), our calculations reveal a third, bright excited doublet state which was not considered previously. This third state possesses the inverse spin polarization on donor and acceptor with respect to the previously studied bright doublet state and is by an order of magnitude brighter, which might be interesting for optically controlling local spin polarizations with potential applications in spin-only information transfer and manipulation of connected qubits.

show abstract

Toward an automated analysis of exchange pathways in spin‐coupled systems

Cited by 12 publications

References 72 publications

Electronic Communication as a Transferable Property of Molecular Bridges?

Electronic Communication as a Transferable Property of Molecular Bridges?

Orbital Entanglement Analysis of Exchange-Coupled Systems

Exchange Spin Coupling in Optically Excited States

Contact Info

Product

Resources

About