2021 Theses Doctoral

Dynamics and spectroscopy of strongly coupled electrons and nuclei

Fetherolf, Jonathan Holmes

This thesis describes work on several research topics in which transport and spectroscopy are influenced by strong electron-nuclear or nuclear-nuclear interactions. First, I give a broad overview of the motivations and background for the main topics covered in this thesis. In the next section, I explore the applicability of perturbative quantum master equations to linear absorption and nonlinear two-dimensional and pump-probe spectroscopies. Next, I introduce a theory of charge transport in organic semiconductors that unifies two popular pictures: incoherent polaron hopping and transient localization due to dynamic disorder. In the next section, I investigate the impact of phonon anharmonicity on the charge transport dynamics of soft semiconductors. Finally, I present a new method of efficiently calculating anharmonic vibrational spectra from ab initio molecular potential energy surfaces.