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Related papers: Computing Hydrogen Tunneling Splittings with Nucle…

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A combined approach that uses the vibrational self-consistent field (VSCF) and vibrational configuration interaction (VCI) method together with the semiclassical instanton theory was developed to study vibrational tunneling spectra of…

Chemical Physics · Physics 2022-02-07 Mihael Eraković , Marko T. Cvitaš

A method for integrating the chemical equations associated with nuclear combustion at high temperature is presented and extensively checked. Following the idea of E. M\"uller, the feedback between nuclear rates and temperature was taken…

Astrophysics · Physics 2007-05-23 Ruben M. Cabezon Gomez , Domingo Garcia-Senz , Eduardo Bravo

Water (H$_2$O) is one of the most abundant molecules in the universe and is found in a wide variety of astrophysical environments. Rotational transitions in H$_2$O + H$_2$O collisions are important in modeling environments rich in water…

Chemical shifts and J-couplings are fundamental parameters in NMR spectroscopy as they provide structural information about molecules. Extracting these quantities from isotopes such as carbon or nitrogen results in reduced sensitivity due…

Quantum Physics · Physics 2025-06-23 P. Alsina-Bolívar , J. Casanova

We extend our previous symmetrized path-integral molecular dynamics approach to calculate tunneling splittings of molecules in rotationally excited states. In this new formalism, the system is rigorously projected onto selected rotational…

Chemical Physics · Physics 2026-04-15 Lea Zupan , Yu-Chen Wang , Jeremy O. Richardson

Strong electric fields can be used to align molecules. However, a non-polar molecule such as H$_2$ has no preference for its orientation. There are thus two equivalent configurations with equal energy separated by a potential-energy…

Chemical Physics · Physics 2025-12-02 J. Amira Geuther , Marit R. Fiechter , Jeremy O. Richardson

A survey is given on the applications of hydrodynamic model of nucleus-nucleus collisons, focusing especially on i) the resolution of hydrodynamic equations for arbitrary configurations, by using the smoothed-particle hydrodynamic approach;…

High Energy Physics - Phenomenology · Physics 2015-06-25 Y. Hama , T. Kodama , O. Socolowski

Quantum tunneling reactions play a significant role in chemistry when classical pathways are energetically forbidden, be it in gas phase reactions, surface diffusion, or liquid phase chemistry. In general, such tunneling reactions are…

Chemical Physics · Physics 2023-03-28 Robert Wild , Markus Nötzold , Malcolm Simpson , Thuy Dung Tran , Roland Wester

The accurate description of nuclear quantum effects, such as zero-point energy, is important for modeling a wide range of chemical and biological processes. Within the nuclear-electronic orbital (NEO) approach, such effects are incorporated…

Chemical Physics · Physics 2022-09-07 Fabijan Pavošević , Sharon Hammes-Schiffer

The United States Department of Energy (DOE) has set ambitious targets for hydrogen storage materials for onboard light-duty cars which are to be achieved by 2027. One of the major problems in solid hydrogen storage materials is the…

Materials Science · Physics 2023-12-12 Sourabh Singha , Abhijit Chatterjee

A procedure for calculation of rotation-vibration states of medium sized molecules is presented. It combines the advantages of variational calculations and perturbation theory. The vibrational problem is solved by diagonalizing a…

Chemical Physics · Physics 2015-04-13 A. I. Pavlyuchko , S. N. Yurchenko , Jonathan Tennyson

For one-neutron halo nuclei, the cross section for elastic scattering and breakup at intermediate energy exhibit similar angular dependences. The Recoil Excitation and Breakup (REB) model of reactions elegantly explains this feature. It…

Nuclear Theory · Physics 2020-12-22 Pierre Capel , Ronald C. Johnson , Filomena M. Nunes

We present a method to calculate neutron scattering cross sections for deformed nuclei using many--body wavefunctions described with multiple reference states. Nuclear states are calculated with the generator coordinate method using a low…

Nuclear Theory · Physics 2025-09-08 J. Boström , J. Rotureau , B. G. Carlsson , A. Idini

The concept of machine learning configuration interaction (MLCI) [J. Chem. Theory Comput. 2018, 14, 5739], where an artificial neural network (ANN) learns on the fly to select important configurations, is further developed so that accurate…

Chemical Physics · Physics 2019-10-31 J. P. Coe

Artificial neural network potentials (NNPs) have emerged as effective tools for understanding atomic interactions at the atomic scale in various phenomena. Recently, we developed highly transferable NNPs for {\alpha}-iron and…

Materials Science · Physics 2023-12-01 Shihao Zhang , Fanshun Meng , Rong Fu , Shigenobu Ogata

The in silico exploration of chemical, physical and biological systems requires accurate and efficient energy functions to follow their nuclear dynamics at a molecular and atomistic level. Recently, machine learning tools gained a lot of…

Chemical Physics · Physics 2020-08-26 Silvan Käser , Oliver T. Unke , Markus Meuwly

We investigate fusion cross section of a nucleus with a valence neutron, using the time-dependent wave-packet method. For a stable projectile, in which the valence neutron is tightly bound (e_n < -3 MeV), the neutron could enhance the…

Nuclear Theory · Physics 2008-11-26 T. Nakatsukasa , M. Ito , K. Yabana , M. Ueda

The hydrogen bond is usually described within the clamped nucleus approximation in which electronic and vibrational motions are considered separately. This approach leads to a double-well potential which facilitates proton tunnelling. In…

Chemical Physics · Physics 2021-12-08 I. Hubač , S. Wilson

The design of moderators and cold sources of neutrons is a key point in research-reactor physics, requiring extensive knowledge of the scattering properties of very important light molecular liquids such as methane, hydrogen and their…

Other Condensed Matter · Physics 2021-04-13 Eleonora Guarini

Recently a new observable to study halo nuclei was introduced, based on the ratio between breakup and elastic angular cross sections. This new observable is shown by the analysis of specific reactions to be independent of the reaction…

Nuclear Theory · Physics 2015-06-17 P. Capel , R. C. Johnson , F. M. Nunes