Chemical Physics
Ground-state electronic structure calculations using Kohn-Sham density functional theory (KS-DFT) offer an unprecedented balance between efficiency and accuracy, now paradigmatic to the fields of quantum chemistry and condensed matter…
We simulate a third-order nonlinear signal in a pump-probe spectroscopy from the interference between first- and second-order wavepackets (WPs), as well as from a state-to-state transition for Stokes and coherent anti-Stokes pathways in the…
We present a computational platform for modeling chemical reactions in complex molecular environments, focused on ligand-protein binding in drug discovery. The platform implements our new quantum-in-quantum-in-classical (QM/QM/MM)…
To further develop accurate and large-scale simulations of electrochemical interfaces, we propose a unified explicit electric potential framework to simultaneously predict atomic forces and electron density distributions. The framework…
The intermolecular interaction between a water molecule and the electrons in aromatic {\pi} systems--the water-{\pi} bond--lies at the heart of many chemical processes, yet its properties remain challenging to measure experimentally and…
Nuclear quantum effects (NQEs) remain a major challenge for molecular simulations, as rigorous treatment requires imaginary-time path-integral methods with heavy computational overhead. Neglecting NQEs leads to systematic errors in…
Accurate prediction of molecular g-tensors for open-shell systems requires a balanced treatment of multireference electron correlation and relativistic spin-orbit coupling. Here, we develop and benchmark spin-orbit quasidegenerate…
All-atom molecular simulation serves as a quintessential ``computational microscope'' for understanding the machinery of life, yet it remains fundamentally limited by the trade-off between quantum-mechanical (QM) accuracy and biological…
A framework for reconstructing the one-electron spinors, $\Gamma_7$ and $\Gamma_8$, of \ch{Cr^3+} ions embedded in glasses from optical measurements has been developed. These spinors provide the basis for calculating the spin-orbital von…
We present El Agente Estructural, a multimodal, natural-language-driven geometry-generation and manipulation agent for autonomous chemistry and molecular modelling. Unlike molecular generation or editing via generative models, Estructural…
For a few decades, Fluorescent Molecular Rotors have been commonly employed as local probes of microviscosity in complex materials. However, without proper calibration, relating microviscosity to a physical parameter is unclear, which…
We show how to add the effects of residual electron correlation to a reference seniority-zero wavefunction by making a unitary transformation of the true electronic Hamiltonian into seniority-zero form. The transformation is treated via the…
We propose a method to solve the electronic Schr\"odinger equation for strongly correlated systems by applying a unitary transformation to reduce the complexity of the physical Hamiltonian. In particular, we seek a transformation that maps…
We show that large language model (LLMs) can be transformed via supervised fine-tuning (SFT) of engineered prompts into SmileyLlama for exploring the chemical space of drug molecules. We benchmark SmileyLlama against pre-trained LLMs and…
Mechanistic understanding and rational design of complex chemical systems depend on fast and accurate predictions of electronic structures beyond individual building blocks. However, if the system exceeds hundreds of atoms, first-principles…
The transient diffusion-limited current at a disk electrode following a change in interfacial ion concentration induced by a potential step is analyzed with direct relevance to chronoamperometric measurements. The mixed-boundary diffusion…
Mixed-reference spin-flip time-dependent density functional theory (MRSF-TDDFT) has recently emerged as an attractive electronic-structure method for studying photochemical processes, given that it bridges the computational efficiency of…
The ethynyl radical cation, CCH$^+$ ($^3\Pi$), offers a unique system for fundamental spectroscopic studies of non-adiabatic effects due to its open-shell linear structure and the presence of a low-lying $^3\Sigma^-$ state, which induces…
The discovery of new energetic materials is critical for advancing technologies from defense to private industry. However, experimental approaches remain slow and expensive while computational alternatives require accurate material property…
Electronic degeneracies and near-degeneracies including conical intersections and avoided crossings, typically accompanied by strong vibronic couplings and nonadiabatic transitions, play fundamental roles in photochemical, photophysical and…