Publications on the project |
001 A comparative STM-investigation of monolayers of n-alkane and arachidic acid on liquid tetradecane-graphite interface |
Authors: | A. I. Senenko, D. V. Stryzheus, A. A. Marchenko, A. G. Naumovets
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Summary: | Highly ordered monolayer films of an n-alkane and arachidic acid were deposited on graphite surface from their solutions in n-tetradecane, and their molecular structure was investigated by scanning tunneling microscopy. Close-packed lamella-like structures with long range order were observed. In alkane monolayers, each lamella is composed by single molecules, while in the case of acid, lamellas consist of dimers formed by acid molecules due to interaction between their carboxylic groups, probably via hydrogen bonds. An increased brightness of carboxyl head in each fifth acid molecule was observed, which is attributed to nonequivalent positions of acid molecules with respect to the substrate carbon atoms. | |
Keywords: | arachidic acid;n-alkanes;graphite;liquid-solid interface;scanning tunneling microscopy | |
Edition: | Materialwissenschaft und Werkstofftechnik | | | 2011,
55-58,English |
001 001 STM-observation of open- and closed-ring forms of functionalized diarylethene molecules self-assembled on reconstructed Au(111) surface |
Authors: | S. Snegir, A. Marchenko, P. Yu, F. Maurel, O.L. Kapitanchuk, S. Mazerat, M. Lepeltier, A. Leaustic, E. Lacaze | |
Summary: | Ordered self-assembled monolayers (SAMs) of thiolated diarylethene photochromic molecules have been built on a Au(111) surface and characterized by mean of scanning tunneling microscopy (STM) for the first time. It has been revealed that molecules deposited from UV-illuminated (closed-ring isomer) and initial solutions (open-ring isomer) both occupy 4 × 2√3 adsorption sites on Au(111) and present a conformation where conjugated parts are parallel to the surface, forming “umbrella-like” structure. On the basis of the distances measured from STM images with intramolecular resolution and on quantum chemical DFT calculations of electronic structure for single molecules, an identical model of molecular packing with a 4 × 4√3 unit cell is proposed for both isomers. The variation of internal orbitals between open- and closed-ring isomers leads to significant change of STM contrast, allowing direct identification of each diarylethene isomer using STM images.Keywords: self-assembly; diarylethene; Au(111); molecular switching
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Edition: | Physical Chemistry Letters | | | 2011,
2433-2436,English |
001 Self-organization of hexadecyl boron acid molecules on atomically flat surface of graphite |
Authors: | А. І. Senenko, A. A. Marchenko, A. G. Naumovets, D. T. Taraschenko, D. A. Glubokov, Ya. Z. Voloshin, A. A. Varzatskiy, A. L. Kapitanchuk | |
Summary: | It has been shown that highly ordered monolayer films of hex-
adecyl boron acid CH3–(CH2)15–B(OH)2 can be obtained on the
basal plane of highly oriented pyrolytic graphite by the deposition from a solution of the acid in n-tetradecane n-C14H30. Using the scanning tunneling microscopy, it has been found that the ordered monolayers have a lamella-like structure. In this structure, each lamella is composed of pairs (dimers) of molecules of the acid. The association of molecules in each pair is implemented through the interaction between B(OH)2-groups. It has been also found that molecules of solvent
n-С14Н30; being at a temperature sufficiently higher than the surface crystallization temperature can be coad-sorbed with molecules of the acid. The coadsorption is explained
by the geometric factor due to a specific size of the dimers of hexadecyl boron acid. | |
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Edition: | Ukrainian Journal of Physics | | | 2011,
1091,Ukrainian |
001 Optoelectronic Properties and Molecular Ordering of Tetracene Thin Layers on Gold |
Authors: | R.D. Fedorovich, V.B. Nechytaylo, L.V. Viduta, T.A. Gavrilko, A.A. Marchenko, A.G. Naumovets, A.I. Senenko, P.V. Shabatyn, J. Baran | |
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Edition: | Spectroscopy Letters | | | 2012,
372-377,English |
001 Structure and electroluminescent properties of thin tetracene layers on gold island films |
Authors: | L. Viduta, T. Gavrilko, A. Marchenko, V. Nechytaylo, A. Senenko, R. Fedorovich, P. Shabatyn
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Summary: | The molecular structure, morphology, and electrical
conductivity of thin tetracene layers obtained by the
thermal vacuum deposition have been studied with the
help of FTIR spectroscopy and STM/STS techniques as
well. It has been shown that this preparation method
does not change the tetracene molecular structure.
The tetracene thin layers on the atomically smooth
pyrolytic graphite surface demonstrate an amorphous
structure. The local current-voltage characteristics
(CVC) measured for tetracene films 10 monolayers
thick show a well-defined asymmetry relative to a tunnel
voltage.
A study of the electrical conductivity and the
electroluminescence (EL) of a planar composite
consisting of gold island films and tetracene layers has
revealed that EL from submicron luminescent centers is
observed on a superlinear section of conduction current
I–V curves. The EL intensity grows with increasing
voltage and becomes maximal at the CVC saturation.
It is found that the EL from the nanocomposite has a
560-nm wavelength emission maximum. | |
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Edition: | Ukrainian Journal of Physics | | | 2012,
260-265,English |
001 001 001 Effect of iron-doped multi-walled carbon nanotubes on lipid model and cellular plasma membranes |
Authors: | S. Prylutska, R. Bilyy, T. Schkandina, A. Bychko, V. Cherepanov, K. Andreichenko, R. Stoika, V. Rybalchenko, Yu. Prylutskyy, U. Ritter, P. Scharff | |
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Edition: | Materials Science and Engineering: C | | | 2012,
1486-1489,English |
001 001 001 Structure and electrochemical properties of aqueous suspensions of single- and multi-walled carbon nanotubes |
Authors: | U. Ritter, N.Tsierkezos, Yu. Prylutskyy, V. Cherepanov, A. Senenko, A. Marchenko, A. Naumovets | |
Summary: | The structure of single- and multiwalled carbon nanotubes (CNTs) functionalized with carboxyl groups in water is investigated by means of atomic force microscopy. The electrochemical properties of the water systems containing both types of CNTs are investigated, by using the cyclic voltammetry and electrochemical impedance spectroscopy techniques. The results may be useful for the clarification of the mechanisms of specific biological activities of CNTs and their applications in various fields of nanobiotechnology.
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Edition: | Ukrainian Journal of Physics | | | 2014,
433-438,English |
001 One-dimensional array of point-like light sources based on gold nanoparticles and tetracene: Preparation and possible operation mechanisms |
Authors: | V.V. Cherepanov, R.D. Fedorovich, O.E. Kiyayev, A.G. Naumovets, V.B. Nechytaylo, P.M. Tomchuk, and L.V. Viduta, | |
Summary: | A method of preparation of a linear close-packed array of point-like light sources based on a nanocomposite of gold nanoparticles and tetracene is proposed. Ordered system of microleads to the light sources with packing density up to 1000 mm−1 consists of linear conducting chains of cobalt nanoparticles self-assembled in a magnetic field. The electroluminescence from the gold-tetracene nanocomposite occurs in the visible range typical of organic light-emitting field-effect transistors based on tetracene. A theoretical substantiation of the possibility of excitation of tetracene molecules by hot electrons emitted from the gold nanoparticles is suggested and compared with other possible physical mechanisms. | |
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Edition: | Applied Physics Letters | | | 2014,
193302-1 – 193302-5,English |
001 Switching at the nanoscale: light- and STM-tip induced switch of a thiolated diarylethene self-assembly on Au (111) |
Authors: | S. Snegir, P Yu, F. Maurel, O. Kapitanchuk, A. Marchenko, E. Lacaze | |
Summary: | The light-induced and STM-tip-induced switching of photochromic thiol functionalized terphenylthiazole-based diarylethene self-assembly on Au(111) has been investigated in ambient conditions. For such a purpose, we took advantage of the formation of highly ordered domains of opened-ring (1o) or closed-ring (1c) diarylethene isomers. We evidenced a STM-tip-induced switching for the 1o isomer characterized by a tip bias threshold of 1000 mV above which switching of all molecules of the ordered 1o domains occurs into the 1c isomer. In contrast, switching from 1c form into 1o form is not observed at the same tunnelling conditions within a domain formed by ordered 1c molecules. We compared tip-induced switching of ordered 1o domains and switching of single 1o isomers embedded in 1c domains. This led to the demonstration that the process of switching of the 1o isomer is determined by geometry of the molecules but also that the stability of the switched 1c isomer depends on the nature of the surrounding isomers. We also compare tip-induced switching and switching under the action of external UV light irradiation of ordered 1o domains. In contrast with STM tip-induced switching, the UV light induces switching of 1o domains into their stable 1c form, in agreement with a collective switching under irradiation, which cannot occur under the action of STM tip. | |
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Edition: | Langmuir | | | 2014,
13275-13282,English |
001 Emergence of chirality in hexagonally packed monolayers of hexapentyloxytriphenylene on Au(111): a joint experimental ans theoretical study |
Authors: | P. Sleczkowski, N. Katsonis, O. Kapitanchuk, A. Marchenko, F. Mathevet, B. Croset, E. Lacaze | |
Summary: | We investigate the expression of chirality in a monolayer formed spontaneously by 2,3,6,7,10,11-pentyloxytriphenylene (H5T) on Au(111). We resolve its interface morphology by combining scanning tunneling microscopy (STM) with theoretical calculations of intermolecular and interfacial interaction potentials. We observe two commensurate structures. While both of them belong to a hexagonal space group, analogical to the triangular symmetry of the molecule and the hexagonal symmetry of the substrate surface, they surprisingly reveal a 2D chiral character. The corresponding breaking of symmetry arises for two reasons. First it is due to the establishment of a large molecular density on the substrate, which leads to a rotation of the molecules with respect to the molecular network crystallographic axes to avoid steric repulsion between neighboring alkoxy chains. Second it is due to the molecule-substrate interactions, leading to commensurable large crystallographic cells associated with the large size of the molecule. As a consequence, molecular networks disoriented with respect to the high symmetry directions of the substrate are induced. The high simplicity of the intermolecular and molecule-substrate van der Waals interactions leading to these observations suggests a generic character for this kind of symmetry breaking. We demonstrate that, for similar molecular densities, only two kinds of molecular networks are stabilized by the molecule-substrate interactions. The most stable network favors the interfacial interactions between terminal alkoxy tails and Au(111). The metastable one favors a specific orientation of the triphenylene core with its symmetry axes collinear to the Au⟨110⟩. This specific orientation of the triphenylene cores with respect to Au(111) appears associated with an energy advantage larger by at least 0.26 eV with respect to the disoriented core. | |
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Edition: | Langmuir | | | 2014,
13275-13282,English |
The events in the framework of the project |
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001 Executant:Institute of Physics, Department of Physics and Astronomy, Section Physical, Engineering and Mathematics 1. Physics of nanostructures Purpose:The development of methods for the controlled formation at the atomic and molecular levels of nanoparticles and nanosystems with predetermined structure and properties based on research of physical laws and mechanisms of nanostructures (including by means of self-organization) Expected results:Release of new product: technology Stage 1:The development of technology for production of self-ordered organic films based on long-chain organic molecules and their derivatives Stage 2:The development of technology for nanoscale research of structures of self-ordered organic monolayers Stage 3:The development of technology for nanoscale research of structures of self-ordered monolayers with switching effects Stage 4:The development of technology of growing and purification of Au and Ag nanocrystals with specified form Stage 5:The development of technology of implementation (incorporation) of metal nanoparticles in the organic matrix
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