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Two novel cycloplatinated complexes that differ by the presence/absence of a lateral fused cyclopenteno ring, respectively, were prepared. Although contributing to only a few percentage of the whole molecular volume, the presence of this aliphatic protuberance appears to be essential for the emergence of liquid crystalline behaviour. This pair of two similar compounds, non-mesomorphic complex and mesomorphic complex, was prepared as a model to assess the possible link of the self-aggregation in solution with the appearance of the liquid crystallinity in molten state. NMR dilution studies in CDCl3 solution and X-ray diffusion study in neat films show qualitative similarity of the aggregated structures formed by liquid crystalline complex. Solution studies may therefore be a useful additional tool to the characterization of the liquid crystalline properties and other self-association processes of Pt(II) complexes. © 2021 We thank Northumbria University, CNRS, University of Strasbourg and Russian Foundation for Basic Research (project No. 18-03-00232A ) for the support of this work.

International audience; We report on the near-field imaging of atomically thin layers of two-dimensional (2D) materials using photoinduced force mapping. This is accomplished by modifying a traditional atomic force microscopy setup to detect optical forces between a nanoscale tip and photoexcited sample. Our setup facilitates the imaging of few-layer flakes of MoS 2 or WS 2 and acquire optical force spectra, both in air and vacuum. The evaluated force spectra in both samples, exhibit the characteristic excitonic resonance peaks that are most typically observed in far-field absorption spectroscopy. We also show that nanoscale defect sites and flake edges can be distinguished from the crystalline flakes with high spectral resolution. Our results pave the way towards gaining a wholesome understanding of optical interactions and structure-property correlations in 2D materials and their heterostructures. Two-dimensional (2D) sheets of atomically thin Van der Waals-bonded crystals have recently opened up new avenues for studying light-matter interactions at the nanoscale. A wide array of candidates including graphene and a palette of transition metal dichalcagonides (TMDs), have fueled the tremendous surge of scientific interest in 2D materials, which demonstrate remarkable optoelectronic

Single molecule magnets (SMM) may be considered for the construction of future integrated nano-devices, provided however that some degree of ordering is imparted to these molecules (surfaces nanostructuration). Combining such nanoobjects with liquid-crystalline orderings to control their assembly and to potentially address them individually therefore appears as one promising strategy. Four mesomorphic, mixed-valent [(Mn8Mn4O12)-Mn-III-O-IV(L-x,L-y,L-z-CB)(16)(H2O)(4)] SMM, differing in the number of liquid-crystalline promoters, (L-x,L-y,L-z-CB), were synthesized, and their self-organizing and magnetic properties were investigated. The influence of the peripheral modifications, and precisely how supramolecular ordering and magnetic properties may be affected by the evolution of the proto-mesogenic cyanobiphenyl-based ligands substitution pattern, was explored. Small-angle X-ray scattering studies revealed that all of the hybridized clusters self-organize into room-temperature bilayer smectic phases, mandated by the specific mesogenic functionalization and that the polymetallic cores are further organized according to a short-range pseudo-2D lattice with hexagonal and/or square symmetry. All mesomorphous hybridized dodecamanganese complexes still behave as SMM: they exhibit blocking of the magnetization at about 2.6 K as evidenced by the occurrence of frequency-dependent out-of-phase ac susceptibility signals as well as an opening of the hysteresis cycle with coercive fields varying between 0.13 and 0.6 T, depending on the surface ligands topology. Comparison of the magnetic properties within this series reveals intricate correlations between the structural features of the mesomorphous molecule magnet (i.e., symmetry of the ligands substitution patterns, molecular conformation, average intercluster distances, and respective inclination) with respect to the relative proportion of slow- and fast-relaxing species and the absolute values of the coercive fields.

New dimer acid-based-polyamides were synthesized with rapeseed oil-based dimer acid (DA) and 1,2-diaminoethane, 1,6-diaminohexane or 1,8-diaminooctane to form DAPAe, DAPAh and DAPAo, respectively. Effects of diamine chain lengths on kinetics evolution as well as on the thermal, physical and mechanical properties of the different polyamides synthesized were investigated. DAPAo was found to be the most reactive diamine because of its higher nucleophilic character. Differential scanning calorimetry (DSC) combined with X-ray diffraction revealed a low-order semi-crystalline structure for all polyamides. A tentative schema for the structural organization of these DAPA is proposed and shows a specific organization with local semi-crystalline segregation domains. DAPAe was found to possess the higher melting temperature likely due to higher crystal cohesion, which was confirmed by higher Young modulus in stress-strain experiments. Rheological data showed an increase of the glass transition temperature concomitantly with the increase of diamine chain length. They also revealed an increase of complex viscosity with the diamine chain length. Investigation of thermal stability showed that DAPAe degrades before DAPAh and DAPAo in connection with the number of methylene units per diamine. © 2010 Elsevier Ltd.