We show that underdamped molecular vibrations fuel the efficient excitation energy transfer in the Fenna-Matthews-Olson molecular aggregate under realistic physiological conditions. By employing an environmental fluctuation spectral function derived from experiments, we obtain numerically exact results for the exciton quantum dynamics in the presence of underdamped vibrationally coherent quantum states. Assuming the prominent 180-cm(-1) vibrational mode to be underdamped, additional coherent transport channels for the excitation energy transfer open up and we observe an increase of the transfer speed towards the reaction center by up to 24%.

The excitation energy transfer dynamics in the Fenna-Matthews-Olson complex is quantified in terms of a non-Markovianity measure based on the time evolution of the trace distance of two quantum states. We use a system description derived from experiments and different environmental fluctuation spectral functions, which are obtained either from experimental data or from molecular dynamics simulations. These exhibit, in all cases, a nontrivial structure with several peaks attributed to vibrational modes of the pigment-protein complex. Such a structured environmental spectrum can, in principle, give rise to strong non-Markovian effects. We present numerically exact real-time path-integral calculations for the transfer dynamics and find, in all cases, a monotonic decrease of the trace distance with increasing time which renders a Markovian description valid.

In this work, the effect of temperature on the electro-oxidation of formic acid on platinum was modeled and numerically investigated. Numerical simulations were carried out using an electrokinetic model recently validated through voltammetric and galvanostatic experiments. We show that the intrinsic electrocatalytic activity of the working electrode for the overall electrochemical reaction can hardly be interpreted from the apparent activation energy due to the complexity of the reaction scheme. A detailed analysis is possible through the estimation of the activation energies determined from the individual rate coefficients. By doing so, we observed that the direct pathway, with an activation energy of 91 kJ mol–1 at 0.40 V and 72 kJ mol–1 at 0.80 V, is the energetically easiest pathway for the formation of CO2 in the proposed reaction scheme. Regarding the self-organized potential oscillations under the galvanostatic regime, our model was able to reproduce experimentally observed results including the phenomena of temperature compensation and overcompensation. Importantly, we have introduced a formalism to classify the elementary steps that contribute to the increase and decrease of the oscillatory frequency in electrochemical systems. Our results shed light on the understanding of the temperature dependence of complex electrocatalytic reactions, and the developed methodology was proven to be robust and of general applicability.

A Pd(II)-catalyzed C(sp 2 /sp 3 )À H bond arylation protocol has been developed to access ortho-diaryl, ortho-mono-aryl, and biaryldiarylmethane-glycinamide derivatives bearing picolinamide as directing group. Mechanistic details of the process have been obtained by computational modelling of the activation reaction through DFT calculations.