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Magnetic measurements of Li-doped MoS2−y nanostructures show a peculiarly large T-independent paramagnetic signal, which cannot be understood in terms of either Curie- or Pauli paramagnetism, or—for that matter—in terms of any simple spin-correlated state, such as antiferromagnetism or superparamagnetic spin clustering. This behaviour appears to be a result of a near-ideal one-dimensional (1D) strongly correlated state, due to the extraordinarily weak inherent coupling between 1D subunits (nanotubes or nanowires), which is an order of magnitude weaker even than in carbon nanotube ropes. In spite of clear evidence for strong electronic correlations from a giant paramagnetic susceptibility, no transition to an ordered state is observed down to very low temperatures and the system appears to be stabilised in a paramagnetic state by fluctuations characteristic of 1D systems. Down to 2 K there is no evidence of a low-temperature quantum critical point. [Copyright &y& Elsevier]

Abstract: The properties of a system of charged particles on a 2D lattice, subject to an anisotropic Jahn–Teller-type interaction and 3D Coulomb repulsion are investigated. Without Coulomb repulsion the system displays a phase transition of first order with global phase separation at low temperature. At long distances Coulomb repulsion always dominates the short-range attraction leading to phase separation on a short scale. On the basis of Monte-Carlo simulation of microscopic lattice-gas model we have formulated an effective phenomenological model. In the limit of low density of polarons, phase separation takes place in the form of charged bubbles. In the limit of high density, charge segregation occurs in the form of charged bubbles and on charged domain walls. [Copyright &y& Elsevier]

Abstract: The infrared photo-induced spectra of the isotope-substituted stoichiometric La2CuO4 samples were studied at T =20K. It was found that the mid-infrared photo-induced absorption spectra of the La2Cu18O4 and La2Cu16O4 do not show any difference within experimental error. It is shown that this observation is consistent with the polaron hopping theory predictions and cannot be used to rule out the polaronic origin of the charge carriers in cuprates. [Copyright &y& Elsevier]

Abstract: It is shown that the ferromagnetic anisotropic clusters are formed at the surface of stoichiometric La2CuO4 fine grains. The hysteresis loops and thermomagnetic irreversibility due to these clusters are observed in a wide temperature range 5–350K. The close similarity of our results to the data on hole-doped cuprates [C. Panagopoulos, M. Majoros, T. Nishizaki, H. Iwasaki, Phys. Rev. Lett. 96 (2006) 047002, and references therein] allows us to propose that the unusual magnetism of the last is the consequence of its intrinsic inhomogeneity. [Copyright &y& Elsevier]

Abstract: Carbon coatings were prepared on various submicrometre-sized particles that can be used as active materials in lithium rechargeable batteries. As a precursor citrate anion was used which, after carbonization at 500–600°C, transforms into a uniform, several-nanometre-thick film that is tightly adhered to the surface of substrate particles. The coatings on Li4Ti5O12 and TiO2 increased significantly the average electron conductivity of cathode composite material, which resulted in a more than 100% increase of reversible capacity at a C/3 rate. Additionally, the coating on TiO2 prevented the gradual deterioration of reversible capacity of this material observed in absence of coating. In cases where due to temperature or atmosphere sensitivity of the substrate, carbon nanocoatings cannot be prepared, we propose the use of conductive polymers. A successful wiring using a sulphonated polyaniline is demonstrated on the example of MoS2 nanotubes. [Copyright &y& Elsevier]

Abstract: A new nanowire-like material with the chemical formula Mo6S3I6 was studied as an additive in a synthetic base oil, a polyalphaolefin (PAO). This material presents interesting friction reducing properties, friction coefficient reaching a value of 0.04 in boundary lubrication. Transmission and scanning electron microscopy, X-ray diffraction, and Raman spectroscopy were used to characterize nanowires before and after friction. The combination of these techniques gave evidence of MoS2 formation in contact area during friction test. This structural evolution of nanowires explains their good friction reducing properties. [Copyright &y& Elsevier]

Abstract: Using a scanning probe microscope, we investigate the structure, electronic and mechanical properties of MoS2–I x nanotubes and Mo6S x I y nanowires. The electronic properties are interestingly very sensitive to the stoichiometry of the nanowires, which can be controlled by adjusting the synthesis conditions. In addition to that, we find also remarkable mechanical properties where molecules can be cut and recombined or deformed without any loss of structural integrity. We demonstrate this by deforming Mo6S x I y nanowires to highly strained configurations without causing irreversible changes to their structures. The rupturing and/or welding process of these nanowires, using AFM manipulation, shows that the molecules stretch to more than 30% of its relaxed configuration before plastic deformation occurs. [Copyright &y& Elsevier]