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Abstract: Salophens and Salens are Schiff bases generated through the condensation of two equivalents of salicylaldehyde with either 1,2‐phenylenediamines or aliphatic diamines, respectively. Both ligands have been extensively exploited as key building blocks in coordination chemistry and catalysis. In particular, their metal complexes have been widely used for various catalytical transformations with high yield and selectivity. Through the modification of the phenol unit it is possible to tune the steric hindrance and electronic properties of Salophen and Salen. The introduction of long aliphatic chains in salicylaldehydes can be used to promote their self‐assembly into ordered supramolecular structures on solid surfaces. Herein, we report a novel method towards the facile synthesis of robust and air‐stable [Al(Salophen)] derivatives capable of undergoing spontaneous self‐assembly at the graphite/solution interface forming highly‐ordered nanopatterns. The new synthetic approach relies on the use of [MeAlIII(Salophen)] as a building unit to introduce, via a simple acid/base reaction with functionalized acidic phenol derivatives, selected frameworks integrating multiple functions for efficient surface decoration. STM imaging at the solid/liquid interface made it possible to monitor the formation of ordered supramolecular structures. In addition, the redox properties of the Salophen derivatives functionalized with ferrocene units in solution and on surface were unraveled by cyclic voltammetry. The use of a five‐coordinate aluminum alkyl Salophen precursor enables the tailoring of new Salophen molecules capable of undergoing controlled self‐assembly on HOPG, and thereby it can be exploited to introduce multiple functionalities with subnanometer precision at surfaces, ultimately forming ordered functional patterns. [ABSTRACT FROM AUTHOR]

Abstract: Cu2+-doped (0–2at%) ZnS nanoparticles stabilized by 2-mercaptoethanol (2-ME) were successfully prepared using wet precipitation route in aqueous solution. The structural and optical characteristics were studied by various techniques. XRD pattern showed zinc blende cubic structure of Cu2+-doped ZnS with grain size of 4±0.5nm. Spherical shape and well distribution of particles is confirmed by TEM, SEM and STM microscopy. Copper doping were identified by elemental dispersive (EDS) spectrometry. UV–vis spectroscopy revealed strong confinement effect due to blue shift in absorption shoulder peak as compared to bulk ZnS. Red luminescence band at∼657nm on Cu2+ doping may be arising from recombination of electrons at sulfur vacancies (V s ) and Cu(t 2) states formed at ZnS band gap. Optimum concentration of 0.25at% (red band) of Cu2+ doping was selected by the observed enhanced PL emission. [Copyright &y& Elsevier]

The atomic surface structure of layered dichalcogenide 1 T-TiSe is studied by scanning tunneling microscopy (STM) at room temperature. In STM images, the ordered structures in the form of 6 ×6 ×6 triangles of Se atoms extending for 0.3 ±0.20 Å above the crystal surface are observed. The effect of a series of different atomic structural defects on the surface topology of titanium disulphide is modeled on the example of isostructural and isoelectronic 1 T-TiS system using the DFTB method. It is determined that a good agreement with the STM experiment is showed by the model of local 1 T-TiS packing defects, where the coordination of titanium atoms changes from the octahedral to the prismatic one. For these systems, the calculation results of the electronic structure and defect formation energy are also presented. [ABSTRACT FROM AUTHOR]