2024/11/11 by Dil K. Limbu, Nathan London, Md Omar Faruque +1 · 1 voice
Chemistry · Mathematics · Physics and Astronomy · #Adiabatic process #Advanced NMR Techniques and Applications #Centroid #Chemistry #Computational chemistry #Curvature #Geometry #Mathematics #Molecular dynamics #Molecular physics #Path integral formulation #Physics #Quantum #Quantum mechanics #Quantum, superfluid, helium dynamics #Spectral line #Spectroscopy and Quantum Chemical Studies #Statistical physics #Thermodynamics #cond-mat.mtrl-sci #cond-mat.stat-mech #physics.chem-ph
paper · pdf · doi:10.1063/5.0248115
arxiv published 2024/11/11 · arxiv updated 2024/11/11 · openalex publication_date 2025/01/03 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/26
Developing efficient path integral (PI) methods for atomistic simulations of vibrational spectra in heterogeneous condensed phases and interfaces has long been a challenging task. Here, we present the h-CMD method, short for hybrid centroid molecular dynamics, which combines the recently introduced fast quasi-CMD (f-QCMD) method with fast CMD (f-CMD). In this scheme, molecules that are believed to suffer more seriously from the curvature problem of CMD, e.g., water, are treated with f-QCMD, while the rest, e.g., solid surfaces, are treated with f-CMD. To test the accuracy of the newly introduced scheme, the infrared spectra of the interfacial D2O confined in the archetypal ZIF-90 framework are simulated using h-CMD compared to a variety of other PI methods, including thermostatted ring-polymer molecular dynamics (T-RPMD) and partially adiabatic CMD as well as f-CMD and experiment as reference. Comparisons are also made with classical MD, where nuclear quantum effects are neglected entirely. Our detailed comparisons at different temperatures of 250-600 K show that h-CMD produces O-D stretches that are in close agreement with the experiment, correcting the known curvature problem and redshifting of the stretch peaks of CMD. h-CMD also corrects the known issues associated with too artificially dampened and broadened spectra of T-RPMD, which leads to missing the characteristic doublet feature of the interfacial confined water, rendering it unsuitable for these systems. The new h-CMD method broadens the applicability of f-QCMD to heterogeneous condensed phases and interfaces, where defining curvilinear coordinates for the entire system is not feasible.