Control over Dethreading Kinetics Allows Evaluating the Entropy Stored in an Interlocked Molecular Machine Out-of-Equilibrium.

The operation of nanomachines is fundamentally different from that of their macroscopic counterparts. In particular, the role of solvent is critical yet rarely associated with machine functionality. Here, we study a minimal model of one of the most advanced molecular machines to gain control of its operation by engineering components and the employed solvent.

Spin-labelled mechanically interlocked molecules as models for the interpretation of biradical EPR spectra.

Biradical spin probes can provide detailed information about the distances between molecules/regions of molecules because the through-space coupling of radical centres, characterised by , is strongly distance dependent. However, if the system can adopt multiple configurations, as is common in supramolecular complexes, the shape of the EPR spectrum is influenced not only by but also the rate of exchange between different states. In practice, it is often hard to separate these variables and as a result, the effect of the latter is sometimes overlooked.

Synthesis and applications of amino-functionalized carbon nanomaterials.

Carbon-based nanomaterials (CNMs) have attracted considerable attention in the scientific community both from a scientific and an industrial point of view. Fullerenes, carbon nanotubes (CNTs), graphene and carbon dots (CDs) are the most popular forms and continue to be widely studied. However, the general poor solubility of many of these materials in most common solvents and their strong tendency to aggregate remains a major obstacle in practical applications.

EPR sensing of metal and organic cations using a novel spin-labelled dibenzo-24-crown-8-ether.

The synthesis of novel dibenzo-24-crown ether substituted nitroxides and their use as spin probes for the detection of cation guests by EPR are reported. Formation of a host-guest complex between the proposed spin probes and several cations, both organic and inorganic, was evidenced by a significant change in the value of the benzylic and nitrogen EPR hyperfine splittings upon complexation. This favorable feature provided a reliable EPR sensor that is able to selectively distinguish different cationic guests.

Synthesis and Characterisation of a Paramagnetic [2]Rotaxane Based on a Crown Ether-Like Wheel Incorporating a Nitroxide Motif.

The synthesis of the new nitroxide crown ether 8 and its use as the wheel in a bistable [2]rotaxane, containing dialkylammonium and 4,4'-bipyridinium recognition sites, is reported. The synthesis of 8 was achieved by the sequential addition of substituted phenyl groups to a nitrone derivatives leading to the preferential formation of the cis stereoisomer. Due to charge-dipole interactions between the nitroxide unit and the bipyridinium moiety, it was possible to probe the movement of the macrocycle between the two molecular stations of the [2]rotaxane after addition of a base by measuring the nitrogen hyperfine splitting in the corresponding EPR spectra.