Resonant inelastic x-ray scattering (RIXS) is a well-established tool for studying electronic, nuclear, and collective dynamics of excited atoms, molecules, and solids. An extension of this powerful method to a time-resolved probe technique at x-ray free electron lasers (XFELs) to ultimately unravel ultrafast chemical and structural changes on a femtosecond time scale is often challenging, due ...

Rotationally resolved electronic spectra of the vibrationless origin and of eight vibronic bands of 5-methoxyindole (5MOI) have been measured and analyzed using an evolutionary strategy approach. The experimental results are compared to the results of ab initio calculations. All vibronic bands can be explained by absorption of a single conformer, which unambiguously has been shown to be the ant...

We report the first spectroscopic study of a complex consisting of a rare earth atom in combination with ammonia. Using two-color resonance-enhanced multiphoton ionization (REMPI) spectroscopy, the lowest energy electronic transition of YbNH(3) has been found in the near-infrared. The spectrum arises from a spin-forbidden transition between the (1)A(1) ground electronic state and the lowest (3)...

A new form of coherent 2D spectroscopy involving a pair of electronic resonances appears to provide several advantages over more established techniques. It can resolve congested peaks and sort them by vibrational quantum number, rotational quantum number, and isotopomer. The high degree of symmetry in the resulting spectra facilitates the ability to assign the quantum numbers and isotopomer for...

Cytochrome P450 enzymes are an important family of biocatalysts that oxidize chemically inert CH bonds. There are many unresolved questions regarding the catalytic reaction intermediates, in particular P450 Compound I (Cpd-I) and II (Cpd-II). By using simple molecular models, we simulate various X-ray spectroscopy signals, including X-ray absorption near-edge structure (XANES), resonant inelas...

This grant led to considerable successes in our work on LAO/STO interfaces. Our efforts have led to two important discoveries, and there are clear paths to follow for subsequent research. Along with our collaborators, we have constructed LAO/STO structures that, for the first time, clearly exhibit depletion upon adjusting a top-gate voltage. Moreover, we discovered these structures can display ...

Rotationally resolved S S fluorescence excitation spectra of 2-methyl anisole (2MA) and 3-methyl anisole (3MA) have been obtained in the environment of a supersonic jet environment. The derived values of the rotational constants show that 2MA itself has a planar heavy-atom structure with trans-disposed methoxy groups in both electronic states. No evidence for any other conformational isomers wa...

The success in creating atomically thin and mechanically robust two-dimensional (2D) crystals, starting with graphene, has unveiled new possibilities for next generation of ultrafast and ubiquitous electronics. One critical distinction between 2D crystals and 3D crystals is that 2D crystals are all-surface materials. Therefore, it is essential to understand how 2D materials interact with their ...

We present a new data acquisition concept using optimized non-uniform sampling and compressed sensing reconstruction in order to substantially decrease the acquisition times in action-based multidimensional electronic spectroscopy. For this we acquire a regularly sampled reference data set at a fixed population time and use a genetic algorithm to optimize a reduced non-uniform sampling pattern....