An Effective Semiclassical Approach to IR Spectroscopy

Abstract

We present a novel approach to calculate molecular IR spectra based on semiclassical molecular dynamics. The main advance from a previous semiclassical method [M. Micciarelli, R. Conte, J. Suarez, M. Ceotto J. Chem. Phys. 149, 064115 (2018)] consists in the possibility to avoid state-to-state calculations making applications to systems characterized by sizable densities of vibrational states feasible. Furthermore, this new method accounts not only for positions and intensities of the several absorption bands which make up the IR spectrum, but also for their shapes. We show that accurate semiclassical IR spectra including quantum effects and anharmonicities for both frequencies and intensities can be obtained starting from semiclassical power spectra. The approach is first tested against the water molecule, and then applied to the 10-atom glycine aminoacid.

References in corpus (9)

• First-Principles Semiclassical Initial Value Representation Molecular Dynamics
• Semiclassical "Divide-and-Conquer" Method for Spectroscopic Calculations of High Dimensional Molecular Systems
• On-the-fly ab initio semiclassical dynamics: Identifying degrees of freedom essential for emission spectra of oligothiophenes
• On-the-fly ab initio semiclassical evaluation of absorption spectra of polyatomic molecules beyond the Condon approximation
• The Importance of the Pre-exponential Factor in Semiclassical Molecular Dynamics
• "Divide and Conquer" Semiclassical Molecular Dynamics: A practical method for Spectroscopic calculations of High Dimensional Molecular Systems
• Validating and Implementing Modified Filinov Phase Filtration in Semiclassical Dynamics
• Application of the Mixed Time-averaging Semiclassical Initial Value Representation method to Complex Molecular Spectra
• On-the-fly ab initio three thawed Gaussians approximation: A semiclassical approach to Herzberg-Teller spectra

Cited by in corpus (5)

• Improved semiclassical dynamics through adiabatic switching trajectory sampling
• Vibrational Investigation of Nucleobases by Means of Divide and Conquer Semiclassical Dynamics
• Semiclassical vibrational spectroscopy with Hessian databases
• Representing Molecular Ground and Excited Vibrational Eigenstates with Nuclear Densities obtained from Semiclassical Initial Value Representation Molecular Dynamics
• A Semiclassical Framework for Mixed Quantum Classical Dynamics