2018/03/20 by Max Buchholz, Frank Großmann, Frank Grossmann +1 · 2 citations
Mathematics · Physics and Astronomy · #Advanced Chemical Physics Studies #Anharmonicity #Atomic physics #Excited state #Hamiltonian (control theory) #Harmonic #Krypton #Mathematical optimization #Mathematics #Physics #Quantum #Quantum mechanics #Quantum, superfluid, helium dynamics #Representation (politics) #Semiclassical physics #Spectral line #Spectroscopy and Quantum Chemical Studies #physics.chem-ph
paper · pdf · doi:10.1063/1.5020144
published as Journal of Chemical Physics 148, 114107 (2018)
openalex publication_date 2018/03/20 · arxiv created 2018/03/21 · arxiv updated 2018/03/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present and test an approximate method for the semiclassical calculation of vibrational spectra. The approach is based on the mixed time-averaging semiclassical initial value representation method, which is simplified to a form that contains a filter to remove contributions from approximately harmonic environmental degrees of freedom. This filter comes at no additional numerical cost, and it has no negative effect on the accuracy of peaks from the anharmonic system of interest. The method is successfully tested for a model Hamiltonian and then applied to the study of the frequency shift of iodine in a krypton matrix. Using a hierarchic model with up to 108 normal modes included in the calculation, we show how the dynamical interaction between iodine and krypton yields results for the lowest excited iodine peaks that reproduce experimental findings to a high degree of accuracy.