Rational design of covalent protein-labeling reagents in complex biological environments requires a molecular-level understanding of how the protein microenvironment governs chemical reactivity; yet, ...

Inverted singlet–triplet (INVEST) materials, characterized by a negative singlet–triplet energy gap (ΔEST), hold great promise for next-generation Organic Light Emitting Diode (OLED) applications. How...

Chemical bonding explains how atoms bind together, but it remains hard to define in universal terms. Here, the authors use quantum entanglement to uncover and quantify bonds in complex systems beyond ...

The Global Natural Orbital Functional (GNOF) provides a straightforward approach to capture most electron correlation effects without needing perturbative corrections or limited active spaces selectio...

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Open-shell hydrocarbons are of great interest in molecular materials, yet their electronic structures remain challenging to describe. Here we investigate triangular acenes, formed by fusing three iden...

Variational quantum eigensolvers (VQEs) are among the most promising quantum algorithms for solving electronic structure problems in quantum chemistry, particularly during the noisy intermediate-scale...

We present a spin-permutation diabatization strategy that transforms ab initio spin-pure eigenstates into spin-localized diabatic states, enabling direct mapping to spin-effective Hamiltonians without projection or orbital localization. The method provides both a real-space decomposition of electronic states in terms of localized spins and a straightforward evaluation of exchange couplings. Applications to several representative systems, including ethylene torsion, prototypical diradicals (benzynes, xylylenes, methylene), trimethylenebenzene triradical, singlet–triplet excited states of organic chromophores, and triplet-pair states in a tetracene dimer, demonstrate that the approach provides magnetic couplings and affords a clear physical interpretation of interacting spins. This general and conceptually transparent framework bridges ab initio electronic structure theory and spin models, and is expected to be especially valuable for systems with nontrivial distributions of unpaired electrons, such as delocalized or strongly correlated molecular magnets and spin-active chromophores.

This figure illustrates the workflow for analyzing excited states using localized molecular orbitals (LMOs). Canonical molecular orbitals (CMOs) from self-consistent field calculations are transforme...

We benchmark second-order perturbative corrections to the Restricted Active Space Configuration Interaction in the hole and particle approximation, RAS(h,p), for valence singlet and triplet excitation...

21st International Conference on Density Functional Theory and its Applications

21st International Conference on Density Functional Theory and its Applications