🔬 Category

physics.chem-ph

1032 papers

This collection explores the fascinating intersection where the laws of physics meet the complex machinery of chemistry. Here, researchers investigate how quantum mechanics governs molecular bonds, how light interacts with matter at the atomic scale, and how fundamental forces shape chemical reactions. It is a realm where abstract mathematical models collide with tangible substances to reveal the hidden mechanisms driving our material world.

On Gist.Science, we process every new preprint in this category directly from arXiv to make these discoveries accessible to everyone. Whether you are a seasoned expert or a curious reader, you will find both plain-language explanations and detailed technical summaries for each paper. Below are the latest contributions from the community pushing the boundaries of physical chemistry.

Theory of Lineshapes in Optical-Optical Double Resonance Spectroscopy

This paper presents analytical and numerical lineshape solutions for molecular Optical-Optical Double Resonance spectroscopy under arbitrary pump and probe field strengths, revealing that while Doppler-free conditions yield Autler-Townes splitting, the inclusion of Doppler broadening results in power-broadened Lorentzian profiles with distinct characteristics for co- and counter-propagating fields and a saturation power significantly higher than that of the bare probe transition.

Kevin K. Lehmann2026-04-03🔬 physics.optics

Freeze-and-release direct optimization method for variational calculations of excited electronic states

This paper introduces a "freeze-and-release" direct optimization method that successfully achieves variational orbital optimization for excited electronic states, particularly charge transfer excitations, by preventing variational collapse and correctly describing energy dependencies without requiring long-range exact exchange, where conventional maximum overlap methods often fail.

Yorick L. A. Schmerwitz, Elli Selenius, Gianluca Levi2026-04-02🔬 physics

Quantifying Local Point-Group-Symmetry Order in Complex Particle Systems

This paper introduces Point Group Order Parameters (PGOPs) as a new set of metrics to directly quantify local point-group symmetry in complex particle systems, demonstrating their superior utility in detecting crystalline order compared to traditional bond-orientational parameters and providing their implementation in the open-source SPATULA software package.

Domagoj Fijan, Maria R. Ward Rashidi, Jenna Bradley, Sharon C. Glotzer2026-04-02🔬 cond-mat.mtrl-sci

Large circular dichroism in the total photoemission yield of free chiral nanoparticles created by a pure electric dipole effect

The authors demonstrate that the intense chiral asymmetry typically observed in photoelectron angular distributions can be translated into a measurable total photoionization yield for submicron-sized chiral nanoparticles, enabling highly sensitive enantiopurity analysis without the need for high-vacuum electron spectrometers.

Sebastian Hartweg, Dusan k. Bozanic, Gustavo A. Garcia-Macias, Laurent Nahon2026-04-02🔬 physics

Orbital Optimization and Neural-Network-Assisted Configuration Interaction Calculations of Rydberg States

This paper presents a method combining variational orbital optimization with plane-wave basis sets and neural-network-assisted configuration interaction to accurately calculate Rydberg states of molecules, overcoming the limitations of traditional diffuse atomic basis sets and achieving results in close agreement with experimental data.

Gianluca Levi, Max Kroesbergen, Louis Thirion, Yorick L. A. Schmerwitz, Elvar Ö. Jónsson, Pavlo Bilous, Philipp Hansmann, Hannes Jónsson2026-04-02🔬 physics

Formation of HNC and HCN isomers in molecular plasmas revealed by frequency comb and quantum cascade laser spectroscopy

This study utilizes quantum cascade laser and frequency comb spectroscopy to detect and quantify hydrogen isocyanide (HNC) and hydrogen cyanide (HCN) in low-temperature N2_2/H2_2/CH4_4 plasmas, revealing a significantly lower HNC/HCN abundance ratio than in interstellar media due to distinct kinetic mechanisms involving vibrationally hot intermediates.

Ibrahim Sadiek, Simona Di Bernardo, Uwe Macherius, Jean-Pierre H. van Helden2026-04-02🔬 physics

Liquid-vapor critical behavior of the TIP4P/2005 water model: effects of NaCl solutes and hydrophobic confinement

Using molecular dynamics simulations with the TIP4P/2005 water model, this study demonstrates that NaCl solutes elevate the liquid-vapor critical temperature and pressure of water while hydrophobic confinement depresses it, employing a validated Binder cumulant method and highlighting the critical importance of accurately accounting for long-range van der Waals interactions.

Mayank Sharma, Peter Virnau2026-04-02🔬 cond-mat

Optical frequency comb Fourier transform spectroscopy of the CH2_279^{79}Br81^{81}Br, CH2_279^{79}Br2_2, and CH2_281^{81}Br2_2 isotopologues in the 1180-1210 cm−1^{-1} region

This paper presents the first high-resolution optical frequency comb Fourier transform spectroscopy study of dibromomethane (CH2_2Br2_2) in the 1180–1210 cm−1^{-1} region, providing precise absorption cross-sections, improved spectroscopic constants for three isotopologues via empirical fitting, and the first ab initio-based line intensities to enable accurate quantitative detection for environmental and exoplanetary applications.

Ibrahim Sadiek, Aleksandr A. Balashov, Adrian Hjältén, Michael Rey, Oleg Egorov, Aleksandra Foltynowicz2026-04-02🔬 physics