Systematic studies on carbon nanotubes synthesis from aliphatic alcohols by a floating catalyst chemical vapour deposition (CVD) route are presented. Solutions of eight aliphatic alcohols (from methanol to decanol) saturated with ferrocene (as the catalyst source) were pyrolysed in a tubular furnace under flowing argon at temperature of 850C. Single-walled carbon nanotubes were obtained from alcohols containing one to six carbon atoms, while carbon feedstocks with longer carbon chains yielded primarily multi-walled carbon nanotubes and carbon-encapsulated magnetic nanoparticles. It was found that the pyrolysis of alcohols containing four to five carbon atoms results in the highest purity of single-walled nanotubes. The length of carbon chain in alcohol molecules also influenced the product crystallinity. The optimum length of the carbon chain was derived from additional thermodynamic calculations.

In this paper we present scanning tunneling microscopy/spectroscopy investigations of multiwall carbon nanotube junctions. We concentrated on bent and narrowing junctions, which my be formed by introducing pentagon–heptagon defects into a hexagonal network of a carbon nanotube. It was expected that the defects introduced to the nanotube could cause changes in the local density of states. The scanning tunneling spectroscopy results were used to search for and identify these defects. We also discuss a hypothesis for a combination of a telescope junction and a pentagon–heptagon induced junction.

We present results of investigation on growth of solid solution crystals with perovskites and K2NiF4 structures used as substrates for epitaxy. Perovskite single crystals with no twins and crystals with K2NiF4 structure with the lattice parameter in the range 3.876-3.819 angstrom and 3.754 to 3.688 angstrom, respectively, can be grown. Here preliminary results on investigation on growth of other solid solution crystals with the lattice constant from 3.946 to 3.688 angstrom are also presented thus covering the whole interesting range for depositing oxide materials. These crystals can be grown by the Czochralski method that secures their high structural quality. Discussed crystals are resistant to. reaction with the deposited oxide layers.

(SrAl0.5Ta0.5O3)1‐x‐y(LaAlO3)x(CaAl0.5Ta0.5O3)y perovskite crystals of general formula ABO3 (where A = Sr1‐x‐yLaxCay and B = Al1/2+x/2Ta1/2‐x/2) were grown by the Czochralski and floating zone methods in wide a composition range. The experiments allowed us to determine regions on the composition diagram where solid solution crystals exist. The structure of the crystals at room temperatures was investigated by X‐ray measurements. Structure of the crystals at constant radius of B‐ions depends on the volume of a primitive perovskite unit cell. Thus, the structure undergoes transition from the cubic lattice of Fm3m + Pm3m space group symmetry through tetragonal (P4/mbm) to orthorhombic (Pbnm) with decreasing the primitive perovskite unit cell volume. One expects that with changing the temperature the crystals undergo second order structural phase transitions but no heat effects by differential scanning calorimetry were observed. There were no twins detected in the crystals with the cubic and tetragonal structures. The range of the lattice parameters variation and the high melting point indicate that these crystals may be used as substrates for HTSc, manganites or GaN epitaxial layers because of their high thermal and chemical stability.

(SrAl0.5Ta0.5O3)(1-x-y)(LaAlO3)(x)(CaAl0.5Ta0.5O3)(y) perovskite crystals of general formula ABO(3) (where A = Sr1-x-yLaxCay and B = Al1/2+x/2Ta1/2-x/2) were grown by the Czochralski and floating zone methods in wide a composition range. The experiments allowed us to determine regions on the composition diagram where solid solution crystals exist. The structure of the crystals at room temperatures was investigated by X-ray measurements. Structure of the crystals at constant radius of B-ions depends on the volume of a primitive perovskite unit cell. Thus, the structure undergoes transition from the cubic lattice of Fm3m + Pm3m space group symmetry through tetragonal (P4/mbm) to orthorhombic (Pbnm) with decreasing the primitive perovskite unit cell volume. One expects that with changing the temperature the crystals undergo second order structural phase transitions but no heat effects by differential scanning calorimetry were observed. There were no twins detected in the crystals with the cubic and tetragonal structures. The range of the lattice parameters variation and the high melting point indicate that these crystals may be used as substrates for HTSc, manganites or GaN epitaxial layers because of their high thermal and chemical stability.

Reaction of C 60 fullerene with ferrocene in the presence of aluminum chloride and aluminum in an inert atmosphere gave ferrocenyl-substituted fullerene 2C 60 ·1.5(C 5 H 5 ) 2 Fe · 3H 2 O. The product is a thermally stable iron-containing carbon cage in which the intersphere cavity is formed by three C 60 polyhedra and is closed by cyclopentadienyl ligands via formation of four carbon-carbon bonds.

We present the basic obstacles to further miniaturization of conventional semiconductor devices. Our disapproval is also addressed to the 0-D, 1-D and 2-D quan- tum devices. After that, we show the principles of operation of molecular electronics devices based on polyphenylene-based chains. Finally, we present our electrical con- ductance measurements recorded on molecules and carbon nanotubes junctions using scanning tunnelling microscopy and spectroscopy. Significance of the results obtained in the field of molecular electronics is briefly outlined.

We present the basic obstacles to further miniaturization of conventional semiconductor devices. Our disapproval is also addressed to the 0-D, 1-D and 2-D quan- tum devices. After that, we show the principles of operation of molecular electronics devices based on polyphenylene-based chains. Finally, we present our electrical con- ductance measurements recorded on molecules and carbon nanotubes junctions using scanning tunnelling microscopy and spectroscopy. Significance of the results obtained in the field of molecular electronics is briefly outlined.

Experiments on the growth of (SrAl0.5Ta0.5O3)1−x−y(LaAlO3)x(CaAl0.5Ta0.5O3)y perovskite crystals by the Czochralski and floating zone methods over a wide composition range are reported. The structure of these crystals was investigated using precise X-ray measurements at room temperature. The experiments allowed us to find regions on a SrAl0.5Ta0.5O3:LaAlO3:CaAl0.5Ta0.5O3 composition triangle where solid solution exists and the type of lattice the crystals adopt. It was found that depending on the volume of the primitive perovskite unit cell, the crystals adopt cubic (Fm-3m+Pm-3m), tetragonal (P4/mbm) and orthorhombic (Pbnm) structures. We did not observe the expected temperature-induced second-order structural phase transitions occurring at the transition from the orthorhombic to tetragonal and from the tetragonal to cubic structures in the 20–600°C range. No tendency to form twins has been detected in the solid solution crystals with the cubic and tetragonal structures. The range of the lattice parameters' variation and the high melting point indicate that these crystals may be used as substrates for high temperature superconductors, manganites or GaN epitaxial layers because of their high thermal and chemical sability.

We describe the synthesis and characterization of aligned carbon nanotubes deposited on quartz substrates by pyrolysis of a xylene–ferrocene mixture at 700 °C at atmospheric pressure. For microscopic characterization of the pyrolyzed products, scanning and transmission electron microscopies and scanning tunneling microcopy were used, and properties of bulk samples were characterized by Raman spectroscopy and x-ray powder diffraction methods. The nanotubes have topological defects and many contain metal particles. Scanning tunneling spectroscopy proved that the nanotubes had a metallic electrical conductivity with resonant states near the Fermi energy. The states are ascribed to the dangling bonds originating from the defects.

Molecules that may adopt various stable conformations might be applied to store information. The conformational changes could be induced by suitable polarized tip of STM. For the STM experiments two types of fullerene: ferrocene cycloadducts (C-60: Fn) were selected where ferrocene fragment is bound to C-60 at the 6-6 bond by different heterocyclic pentagon rings. According to semiempirical quantum chemistry calculation one of them may be used to STM observation without any modification, while the second cycloadduct must be exposed to thermal treatment in order to obtain bistable molecule.

Physicochemical properties of carbon nanotube surfaces by means of the special thermogravimetry (Q-TG), sorptometry and atomic force microscopy (AFM) methods were investigated. A numerical and analytical procedure for the evaluation of total heterogeneous properties (desorption energy distribution and pore-size distribution functions) on the basis of liquid thermodesorption from the sample surfaces under the quasi-equilibrium conditions and sorptometry techniques are presented. The desorption energy distribution was derived from the mass loss Q-TG and the differential mass loss Q-DTG curves of thermodesorption of pre-adsorbed polar and apolar liquid films. For the first time, the evaluation of the fractal dimensions of nanotubes using the sorptometry, Q-TG and AFM data are presented.

Experiments on growth of (SrAl0.5Ta0.5O3)1−x(LaAlO3)x perovskite crystals by the Czochralski and floating zone methods in whole composition range are reported. The structure of these crystals was investigated by precise X-ray measurements at room and elevated temperatures. The experiments allowed us to propose a schematic phase diagram of this solution; solid solutions exist at a concentration of 0⩽x⩽0.5 when crystals assume a cubic structure. The Czochralski method may be used to grow single crystals with a composition x=0.23–0.41. Neither any structural phase transition nor tendency to form twins was detected in these solid solution crystals. The lattice parameters, thermal expansion coefficient and high melting point close to 1850°C indicate their high thermal and chemical stability and prove that these crystals may be used as substrates for high-temperature superconductor, manganites or GaN epitaxial layers.

The C60ONCC5H4FeC5H5 cycloadduct was prepared in the reaction between C-60 and ferrocene oxime. The compound dissolved in dichloroethane was deposited on HOPG and observed by UHV STM/STS methods. The molecules Of C(60)ONCFn formed long straight chains extending for several microns, and in some of the chains the adducted groups were clearly visible. The dI/dV(V) plots exhibit pronounced maxima interpreted as resonance tunneling to molecular discrete electronic states. The STM/STS observations are discussed within the terms of semiempirical quantum chemical molecular modeling.

The C60ONCFn cycloadduct (Fn=ferrocene) was prepared in the reaction between C60 and ferrocene oxime, the ferrocene derivative was bound to C60 at the 6–6 bond by a heterocyclic oxygen–nitrogen–carbon ring; the compound was stable in air. The compound dissolved in dichloroethane was deposited on HOPG and observed by UHV STM/STS methods. The molecules of C60ONCFn formed several-microns-long straight chains with clearly visible adducted groups pointing to one side of the chain. The STM/STS observations are discussed within the terms of semiempirical quantum chemical molecular modeling.

Using special thermogravimetry and sorptometry methods physicochemical properties of carbon nanotube surfaces were investigated. A numerical and analytical procedure for the evaluation of total heterogeneous properties (desorption energy distribution and pore-size distribution functions) on the basis of liquid thermodesorption from the sample surfaces under the quasi-equilibrium conditions are presented. The desorption energy distribution was derived from the mass loss Q-TG and the differential mass loss Q-DTG curves of thermodesorption of pre-adsorbed polar and apolar liquid films. It is shown that the samples are highly sensitive to benzene vapour because the mechanism of liquid adsorption depends largely on the active surface centres and molecular interactions. For the first time, the evaluation of the fractal dimensions of nanotubes using the sorptometry and thermogravimetry data is presented.

Preparation of fullerites containing cobalt and analyses of reactions based on semiempirical quantum calculations are described. The magnetic properties of thermally treated C60Co3 samples: Curie constant (C≈3500emuK/molOe) temperature and field dependencies of magnetization and nonequilibrium effects of magnetization are interpreted in terms of superparamagnetic blocking model of the compound.