High-precision THz (30 to 360 cm −1 ) spectra of bulk liquid water are presented from ambient conditions up to hydrostatic pressures of 10 kbar. In concert with ab initio simulations, this allows us to characterize the molecular-level changes of the H−bond network under solvent stress conditions. Both the experimental and theoretical THz spectra reveal a blue shift in the intermolecular translational mode at 180 cm −1 by 40 cm −1 at 10 kbar and a blue shift together with an intensity increase in the relaxation mode. These changes can be traced back to a pressure-induced increase of the population of so-called short H−bond double donor configurations at the expense of those with longer such intermolecular bonds. Distinct electronic polarization effects are critical to capture the characteristic intensity changes of the THz line shape function. These advances in high-pressure THz spectroscopy open the door to investigate the pressure response of solvation shells and solute−solvent couplings.

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The influence of β-lactoglobulin (βLG) on the fast sub-picosecond collective hydration dynamics in the solvent was investigated by THz absorption spectroscopy as a function of pH. It is well-known that a change in pH from pH 6 to pH 8 reversibly opens or closes the binding cavity by a transition of the E-F loop. Furthermore, the aggregation of the protein into dimers is affected, which is thought to be triggered by changes in the enzyme's electrostatic potential. Our data reveal that pH has a clear influence on the THz absorption of βLG. We discuss this influence in light of the changes observed in the sub-psec solute/solvent dynamics when probed by THz spectroscopy, which are, in turn, seen to correlate with changes in the pH value.

The manipulation of carbon nitride (CN) structures is one main avenue to enhance the activity of CN‐based photocatalysts. Increasing the efficiency of photocatalytic heterogeneous materials is a critical step toward the realistic implementation of sustainable schemes for organic synthesis. However, limited knowledge of the structure/activity relationship in relation to subtle structural variations prevents a fully rational design of new photocatalytic materials, limiting practical applications. Here, the CN structure is engineered by means of a microwave treatment, and the structure of the material is shaped around its suitable functionality for Ni dual photocatalysis, with a resulting boosting of the reaction efficiency toward many CX (X = N, S, O) couplings. The combination of advanced characterization techniques and first‐principle simulations reveals that this enhanced reactivity is due to the formation of carbon vacancies that evolve into triazole and imine N species able to suitably bind Ni complexes and harness highly efficient dual catalysis. The cost‐effective microwave treatment proposed here appears as a versatile and sustainable approach to the design of CN‐based photocatalysts for a wide range of industrially relevant organic synthetic reactions.

The bottom-up design of smart nanodevices largely depends on the accuracy by which each of the inherent nanometric components can be functionally designed with predictive methods. Here, we present a rationally designed, self-assembled nanochip capable of capturing a target protein by means of pre-selected binding sites. The sensing elements comprise computationally evolved peptides, designed to target an arbitrarily selected binding site on the surface of beta-2-Microglobulin (β2m), a globular protein that lacks well-defined pockets. The nanopatterned surface was generated by an atomic force microscopy (AFM)-based, tip force-driven nanolithography technique termed nanografting to construct laterally confined self-assembled nanopatches of single stranded (ss)DNA. These were subsequently associated with an ssDNA–peptide conjugate by means of DNA-directed immobilization, therefore allowing control of the peptide’s spatial orientation. We characterized the sensitivity of such peptide-containing systems against β2m in solution by means of AFM-based differential topographic imaging and surface plasmon resonance (SPR) spectroscopy. Our results show that the confined peptides are capable of specifically capturing β2m from the surface–liquid interface with micromolar affinity, hence providing a viable proof-of-concept for our approach to peptide design.