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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
A fluctuating quantum model of the CO vibration in carboxyhemoglobin
1Institut des Sciences Moléculaires d'Orsay, UMR CNRS 8214, Université Paris-Sud 11, 91405 Orsay, France. cyril.falvo@u-psud.fr
Abstract:
In this paper, we present a theoretical approach to construct a fluctuating quantum model of the CO vibration in heme-CO proteins and its interaction with external laser fields. The methodology consists of mixed quantum-classical calculations for a restricted number of snapshots, which are then used to construct a parametrized quantum model. As an example, we calculate the infrared absorption spectrum of carboxy-hemoglobin, based on a simplified protein model, and found the absorption linewidth in good agreement with the experimental results.
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