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Despite a huge expansion of research on compositionally complex alloys, CCA (such as the entropy alloys, HEA and the corresponding glassy alloys) their comprehension is still limited, which is detrimental both for the design of CCAs and for their application. The broad compositional range in CCAs enables simple tuning of their properties by varying the contents of their constituent elements. Accordingly, the study of transition from CCA to conventional alloy, CA composed from the same constituents is important, both for understanding the formation of solid solutions in CCAs and for proper evaluation of their potential with respect to that of CAs. However, this transition has so far been studied systematically in only two types of alloys: isopleths of the Cantor alloy and glassy TiZrNbCuNi/Co alloys with variable Co, Ni or Cu content (Materials 14 (2021) 5824 and ref. therein). In both alloy systems the variation of a given property with composition depends sharply on the selected principal component and can be either monotonic (like that in the ideal solid solution) or non-monotonic. When the variation is non- monotonic, the maximum value of the selected property is usually outside of HEA composition range.

Since its discovery, graphene has become a very interesting material for the application in a variety of fields, such as photonics, plasmonics, spintronics or nanoelectronics. It is attracting ever growing interest due to its remarkable properties which have origin in graphene’s crystal and electronic structure. The electronic structure of graphene was resolved in angular-resolved photoemission (ARPES) experiments and its most characteristic feature is a Dirac cone. The Dirac cone could be modified in interaction with the substrate by charge carriers doping or by structural modification. We have studied a periodically modulated graphene grown on Ir(332) substrate where graphene growth induces reversible, well defined faceting of iridium surface into alternating terraces and step bunches which we investigated in scanning tunneling microscopy (STM) experiments [1][2]. Measurements of the electronic band structure by ARPES showed the Dirac cone anisotropy which was attributed to the 1D periodicity present in the system and lateral variation of the charge carrier concentration (on terraces and step bunches) [2]. [1] Šrut, Iva ; Mikšić Trontl, Vesna ; Pervan, Petar ; Kralj, Marko ; Temperature dependence of graphene growth on a stepped iridium surface.// Carbon 56 (2013) ; 193-200 [2] Iva Šrut Rakić, Marko Kralj, Wouter Jolie, Predrag Lazić, Wenhao Sun, José Avila, Maria- Carmen Asensio, Fabian Craes, Vesna Mikšić Trontl, Carsten Busse, and Petar Pervan ; Step-induced faceting and related electronic effects for graphene on Ir(332) // Carbon 110, (2016) 267-277

Despite a huge expansion of research on compositionally complex alloys, CCA (such as the approximately equimolar, multi-component high- entropy alloys, HEA and the corresponding high- entropy glassy alloys), their basic understanding is still limited, which is detrimental both for the design of CCAs and for their application. In particular, the prediction of compositions capable of forming random solid solutions (RSSs) and the prediction of their properties is still a problem. Nevertheless, some properties of a few CCAs exceed those of conventional alloys (CA) [1].

Metal doped silica glass is widely used in photonics, photoelectronis, optics as well as in sensing. There are several methods for doping the glass matrix with metal ions, such as often used melted salt ion exchange and much cheaper and simpler process called electric field assisted dissolution (EFAD), used in our laboratory 1-3. In EFAD process, thin metal films deposited on glass substrate by electron beam evaporation are subjected to moderately elevated temperature and DC voltages. Resulting current induces several consecutive processes: 1) drifting of naturally present alkali metal ions in glass matrix toward cathode, leaving the subanodic layer depleted of charge carriers ; 2) dissolution of thin metal film and 3) subsequent travelling of dissolved metal ions into the subanodic layer. Unfortunately, the doping process is still not completely unveiled. Therefore, the elucidation of the process itself is extremely important. Herein we present ellipsometry based results of the optical properties of Al or Cu EFAD doped glass. Doping with metal ions and depletion from alkali ions are processes that take place simultaneously, but each with its own dynamics. As a consequence, the refractive index in the subsurface layer of the EFAD doped glass changes with the course of the process. Besides this, the refractive index is not constant through the thickness of the affected region since concentration of the dopant metal ions, as well as alkali ions, is not homogeneously distributed.

Various glass samples were poled using high temperature and electric field. Optical characterization and SIMS of samples were performed. SIMS measurements were compared to numerical simulations of atomic ratio depth profiles.

We present results of comprehensive study of electronic properties of (TiZrNbCu)(1-x)Ni(x) metallic glasses performed in broad composition range x encompassing both, high entropy (HE) range, and conventional Ni-base alloy concentration range, x >= 0.35. The electronic structure studied by photoemission spectroscopy and low temperature specific heat (LTSH) reveal a split-band structure of density of states inside valence band with d-electrons of Ti, Zr, Nb and also Ni present at Fermi level N(E_F), whereas LTSH and magnetoresistivity results show that variation of N(E_F) with x changes in Ni-base regime. The variation of superconducting transition temperatures with x closely follows that of N(E_F). The electrical resistivities of all alloys are high and decrease with increasing temperature over most of explored temperature range, and their temperature dependence seems dominated by weak localization effects over a broad temperature range (10-300 K). The preliminary study of Hall effect shows positive Hall coefficient that decreases rapidly in Ni-base alloys., 32 pages, 6 figures

In metallic systems electronic structure determines almost all their properties. Therefore, a change in properties of multicomponent alloys on crossing from HEA to conventional alloy concentration range in the same alloy system reflects the corresponding change in ES.

Electric field assisted dissolution (EFAD) is a process in which metal nanoparticles on the surface of the substrate dissolve and drift away from the anode into the bulk of the substrate under the influence of the applied electric field and moderately elevated temperature. There is a significant interest in EFAD due to its possibility to imprint the image of anodic electrode structure in glass- metal nanocomposites. EFAD can also be utilized for developing novel bio-, chemical and environmental sensors. Recently, microstructuring of conductive thin silver layers have been obtained using EFAD. Copper and aluminium are materials interesting for microstructuring because of their good conductivity, they are abundant and consequently, relatively cheap. It would be useful to find the maximum conductive microstructure thickness that can be achieved by reasonable EFAD conditions using these materials. For this purpose, copper, aluminium, and silver thin layers were deposited onto soda-lime glass substrate using electron beam evaporation. Different magnitudes of electric field, temperature and duration of EFAD were applied to these layers. Measurements of the obtained samples optical properties is done by ellipsometry followed by optical characterization. The limitations of EFAD process applied for microstructuring of conductive metal layers, same as guidelines for further research were obtained. Therefore could be used for photocurrent enhancement. With the spin coating method, we synthesized gold, silver and copper nanoparticles on a glass substrate. Combining different ratios of different metal precursor salts it is possible to obtain interesting optical properties. By changing the temperature and time of annealing of the substrates as well as the metal salt concentration and a choice of a solvent for the spin coating, it is possible to manipulate the shape and size of metal nanoparticles on the substrate.

The study of transition from conventional concentrated alloys to high-entropy ones composed from the same elements is apparently very important, both for understanding the formation of HEAs and for proper evaulation of their potential with respecct to that of corresponding CAs.

We present the results of ongoing comprehensive study of the electronic properties of (TiZrNbCu)1- xNix metallic glasses performed in a broad composition range x encompassing both, the high entropy (HE) range, x ≤ 0.25, and conventional Ni- base alloy concentration range, x ≥ 0.35. The electronic structure (ES) studied by photoemission spectroscopy and low temperature specific heat (LTSH) [1] reveal the split-band structure of the density of states (DoS) inside the valence band with the d- electron of Ti, Zr, Nb and also Ni present in DoS at the Fermi level N(EF), whereas LTSH and present magnetoresistivity results show that variation of N(EF) with x changes in Ni-base regime. The variation of the superconducting transition temperatures, TC ≤ 1.6 K with x closely follows that of N(EF) as is usual in disordered transition metal alloys [2]. The electrical resistivities of all alloys are high (> 150 µΩ cm) and accordingly decrease with increasing temperature over most of the explored temperature range, and their temperature dependence seems dominated by the weak localization effects over a broad temperature range (10 – 300 K). The preliminary study of the Hall effect shows that the Hall coefficient RH > 0 and in the HE concentration range change little with x. The results are compared with these for corresponding binary metallic glasses. [1] I. A. Figueroa, et al., J. Alloys Compd. 745, 455 (2018) [2] E. Tafra, et al., J. Phys.: Condens. Matter 20, 425215 (2008)

On cooling of molten alloy the formation of metallic glass (MG) competes with that of intermetallic compounds (TC). This competition determines glass forming ability (GFA) of a given alloy and in binary alloys GFA can be expressed in terms of the formation enthalpies of MG and competing TCs [1]. More recently we have shown that a similar electronic structure, ES, (represented by the density of states (DoS) at the Fermi level, N(EF)) of competing TCs to that of MG enhances GFA in Cu-Hf, Zr alloys [2]. In particular, we found that small difference between the N(EF)-dependent properties (such as magnetic susceptibility (χ) and Sommerfeld coefficient (γ)) of as-cast and crystallized MGs reflects an enhanced GFA. Combining our and literature results for N(EF) and χ we show here that this correlation holds in all binary (Cu, Ni-Ti, Zr, Hf) and ternary (Cu-Hf-Ti, Cu-Zr-Al) alloys of early (TE) and late (TL) transition metals for which there exist relevant data. The correlation between ES and GFA shows up the best in Cu-Zr and NiZr2 alloys in which the data for change in N(EF) upon crystallization exist. The applicability of this correlation (GFA criterion) to all TE-TL alloys is supported by photoemission studies and low temperature specific heat measurements [3] which show similar composition dependencies irrespective of the number of components in the alloy. _____________________________________________ ∗ This work was supported by UNAM-DGAPA-PAPIIT project No. IN101016 and Osijek University project IZIP2016-3. † [1] R. Ristić et al., J. Alloys and Compd. 621 (2015) 136 ; [2] K. Biljaković et al., J. Alloys Compd. 695 (2017) 2661 ; [3] R. Ristić et al. EPL , 114 (2016) 17006.

High-entropy alloys (HEA) are new type of alloys based on multiple (≥5) principal alloying elements [1). This design enables research and probable exploitation of a huge number of new alloys with structures and properties which can hardly be anticipated [2]. For obvious reason and also due to often inadequate strategy of research [3], the conceptual understanding of HEA is quite limited which hampers their development. After brief introduction in HEA we present main results of a parallel study of local atomic structure, electronic structure (including first ever photoemission spectroscopy study of HEA) and selected properties of (TiZrNbCu)1-xNix (x≤0.5) amorphous alloys, which sheds more light into their interrelationship and also enables direct comparison of HEA with conventional Ni-rich alloys (x≥0.35). Our results challenge some myths commonly employed in descriptions of HEA [2]. [1] B. Cantor, I. T. H. Chang, P. Knight, A. J. B. Vincent, Mat. Sci. Eng. A 375-377 (2004) 213. [2] E. J. Pickering, N. G. Jones, Inter. Mater. Rev. 61 (2016) 183, and references therein. [3] K. Biljaković et al , J. Alloys Compd. 695 (2017) 2661.

The study of producing graphene extends from mechanically exfoliated graphene fl akes transferred to diff erent substrates to chemical vapor deposition (CVD) growth process on diff erent metal surfaces. The most frequently used carbon source in CVD process is ethylene. To obtain a single domain (R0) graphene on Ir(111) surface from ethylene high growth temperature (~1000°C) is required. As already reported, reduction of growth temperature is realized by using aromatic carbon sources in CVD process on Cu(111) in the region of atmospheric pressure [1]. The use of benzene reduces the growth temperature as low as 300°C. This fi nding opens the opportunity to the possibility of low temperature growth on Ir(111), but in ultra high vacuum (UHV) conditions. To investigate this possibility we used scanning tunneling microscopy (STM) and low energy electron diff raction (LEED). Our fi ndings point to the CVD growth with predominantly R0 oriented graphene achieved at 700°C.

Graphene, an atomically thin sheet of carbon atoms, is a promising candidate for many future applications due to its extraordinary physical properties [ref]. Additionally, these properties can be modified by creation of various graphene hybrid structures where graphene is combined with other substances into a new system. Intercalation of epitaxial graphene is one of the routes to such novel systems. Even though intercalation of epitaxial graphene is studied by many authors, the mechanism governing it i.e. a microscopic view of an atom transport across the graphene sheet is still unclear. Here we present a study of a cesium + graphene/Ir(111) system at various stages. By utilizing scanning tunneling microscopy (STM) we were able to characterize emerging structures at the atomic scale. Complementary, low-energy electron microscopy (LEEM) revealed cesium intercalation and desorption dynamics in real time on micron scales. Angle-resolved photoemission (ARPES) was used to characterize chemical doping of graphene. Density functional (DFT) calculations were performed in order to gain more insight into the driving forces of intercalation. In the experiments we clearly observe a phase separation of cesium deposited on epitaxial graphene. For low coverage, a dilute phase of cesium adatoms is formed on top of graphene. As more cesium is added, an additional phase forms which corresponds to the cesium atoms being intercalated under the graphene in ~15 times denser structure. Therefore intercalation occurs when a critical value of adatom concentration is reached. Only then it pays off energetically to the cesium atoms to go under the graphene at the cost of delamination energy which has its origin in the van der Waals binding of graphene to the iridium. The two cesium phases can coexist and are separated by a sharp interface. Besides topographical differences, the two phases also give rise to different electronic structures of graphene. We found that transport of cesium to the intercalated phase takes place at graphene wrinkles which contain nano-cracks. Our results contribute to the understanding of intercalation under graphene in detail and can be used to form more general picture of intercalation of epitaxial graphene and other modern layered materials.

Adsorption and intercalation of various substances to epitaxial graphene gives rise to hybrid systems with novel topographical and electronic properties [1]. One of the most commonly used intercalation substances are alkali atoms know for their high levels of chemical doping of graphene [2, 3]. However, the mechanism of alkali intercalation i.e. a microscopic view of an atom transport across the graphene sheet is still unclear. Here we present a study of a cesium + graphene/Ir(111) system at various stages involving cesium adsorption, intercalation, and desorption. By utilizing scanning tunneling microscopy (STM) we were able to characterize emerging structures at the atomic scale. Complementary, low-energy electron microscopy (LEEM) revealed cesium intercalation and desorption dynamics in real time on micron scales and clearly showed a strong influence of graphene wrinkles and iridium steps on the intercalation process. Angle-resolved photoemission (ARPES) was used to characterize chemical doping of graphene on individual phases. In detail, we have shown that cesium atoms do not intercalate immediately once they are deposited on the graphene surface. First they form a diluted “on top” phase up to a maximum (7×7) concentration. Denser phases of adsorbed Cs are energetically less favorable and it pays off to intercalate cesium atoms below graphene at a cost of its delamination from the substrate. We found that it is possible to achieve coexistence of well defined “on top” and intercalated Cs-phases. Transport of cesium under graphene takes place at cracks on graphene wrinkles. The desorption process revealed once more the importance of graphene topography and in particular the delamination/relamination processes to the dynamics of such hybrid systems. Our results contribute to the understanding of intercalation under graphene in detail and can be used to form more general picture for graphene intercalation with other chemical species. [1] R. Balog et al., Nature Mater. 9, 315 (2010) [2] J.L. McChesney et al., Phys. Rev. Lett. 104, 136803 (2010) [3] I. Pletikosić et al., Phys. Rev. B 155447 (2012)

Interclation of alkali atoms is a straightforward route for the chemical doping of epitaxial graphene (G). This has been demonstrated for graphene on SiC [1] as well as for graphene on metals [2], where dopings/shifts of the Dirac cone at the K-point near the Fermi level have been followed by angle-resolved photoemission spectroscopy (ARPES). However, ARPES is area-averaging technique which does not provide a clear picture on the process of the penetration of alkali atoms to a position between graphene layer and its support. Our ARPES studies for intercalation of Li, Na, K, and Cs to G/Ir(111) have indicated that dynamics of alkali intercalation depend on the size of the alkali atom and we have focused to the intercalation of large alkali atom, Cs. By the combination of ARPES, scanning tunneling microscopy and low- energy electron microscopy we reveal two different doping effects from Cs on top and intercalated compact layer which is formed by a diffusion of Cs atoms through wrinkles network of graphene. [1] J. L. McChesney, et al., Phys. Rev. Lett. 104, 136803 (2010). [2] M. Bianchi, et al., Phys. Rev. B 81, 041403(R) (2010).

The growth of large-scale uniform graphene on flat Ir(111) is today well established. The graphene produced by thermally activated catalytic decomposition of ethylene forms a (9.32 x 9.32) moiré superstructure. The moiré structure gives rise to superperiodic potential which forms replica bands and opens minigaps in the π-band of graphene (Dirac cone). Motivated by the possibility to further modify the Dirac cone, e.g. by additional 1D periodic potential introduced by substrate, we have studied the growth and performed scanning tunnelling microscopy (STM) and low energy electron diffraction (LEED) investigation of graphene on vicinal Ir(332) surface. The structural properties of graphene grown by temperature controlled growth (TPG) and chemical vapour deposition (CVD) by varying sample temperature and ethylene pressure have been characterized. LEED results show that the growth process alters the long-range uniformity and 1.1 nm periodicity characteristic for a pristine Ir(332) surface, which is upon graphene growth characterized by new periodicity of much smaller length. STM study of the topology shows that periodic narrower steps are formed but also flat (111) areas, indicating the reshaping of the substrate by step bunching. The width of new formed terraces and degree of step order can be influenced by sample temperature during CVD. We have identified at least three distinct rotational variants of graphene resulting in different moiré patterns. With the insight in the atomic arrangement of carbon lattice on terraces and at the step edges a link between moiré pattern and edge properties is established.

A well established route for the large-scale production of graphene is chemical vapor phase deposition (CVD) growth on various metal substrates [1]. However, in order to obtain highly oriented graphene cov- ering the entire Ir(111) surface one needs to combine the temperature programmed growth (TPG) with CVD [2]. Moreover, by using just the TPG procedure, it is possible to grow graphene fl akes of various aver- age sizes, depending on the growth parameters used. The overall area of Ir(111) sample covered with fl akes after each TPG cycle is always the same, regardless of the temperature [3]. Here we report a study of graphene fl akes obtained by ethene decomposition on Ir(111) using the TPG procedure at various temperatures. As the decomposition temperature of the preadsorbed ethene increases, the average size of the flakes increases as well. Based on angle- resolved photoemission spectroscopy (ARPES), in particular the Dirac cone intensity analysis, we characterise graphene fl akes on Ir(111) of varying sizes and compare these results with known STM and XPS data. [1] X. Li et al., Science 324, 1312 (2009) [2] R. von Gastel et al., Appl. Phys. Lett. 95, 121901 (2009) [3] J. Coraux et al., New J. Phys. 11, 023006 (2009)

We have performed combined angle resolved photoemission spectroscopy (ARPES) experiments and density functional theory (DFT) calculations of the electronic structure of Ir(111) surface, with the focus on the existence of energy band gaps. The investigation was motivated by the experimental results suggesting Ir(111) as an ideal support for the growth of weakly bonded graphene. Therefore, our prime interest was electronic structure around the K symmetry point. In accordance with DFT calculation, ARPES has shown a wide energy band gap with shape of parallelogram centred around the K point. Within the gap three surface states were identified ; one just below the Fermi level and two spin-orbit split surface states at the bottom of the gap.

We present experimental study of the growth mode and electronic properties of ultra-thin silver films deposited on Ni(111) surface by means of scanning tunnelling microscopy (STM) and high resolution angle resolved photoemission spectroscopy (HR-ARPES). The formation of the 4d-quantum well states (QWS) was found in agreement with the Stranski-Krastanow growth mode of Ag(111). The electronic structure of the 1 ML film is consistent with the silver layer which very weakly interacts with the supporting surface. The analysis of the lineshape of Ag-4d QW states suggests strong localization of the electronic states within the silver layer but at the same time the decay of the photo-hole appears to be influenced by the dynamics of the electrons in the supporting surface.

U ovom radu su pokazani rezultati istraživanja elektron-fonon vezanja pi-vrpci grafena na Ir(111) interkaliranog alkalijskim metalima.

Spin-split two-dimensional (2D) states which can, for instance, be realized in magnetically stabilized surface alloys, are of immense technological interest for new spintronic devices. We have studied the interaction of manganese with a Cu(111) surface using different surface sensitive techniques. STS at low temperature indicates no observable Kondo-effect for single Mn atoms. Formation of the surface alloy first leads to the quenching of the Cu(111) surface state. Our results indicate none or very weak magnetic and spin-splitting effects for Mn/Cu(111).

STM and HRARPES study of extremely thin silver films on Ni(111)

We have studied electronic and structural properties of ultra thin Ag films deposited on Ni(111) by HRARPES and STM. The HRARPES experiments were focused mainly on the development of the Ag 4d bands. Of particular interest was the segment of the 4d band lying in the projected energy gap of the Ni substrate where Ag d states are quantized. To resolve between individual d-QWS due to their large number in the relatively narrow energy range, high energy resolution is required. In our experiments, the resolution < 25 meV was estimated for He I line. The interpretation of the spectra of multilayer Ag d-QWS is also complicated by the fact that already after the completion of first layer, the next two layers grow simultaneously, as shown by our STM study. For 3ML nominal coverage, the photoemission spectrum is dominated by the peak at 4.84 eV, corresponding to the energy of the direct transition peak from Ag(111) surface for the He I excitation energy. Spectrum for the 7ML nominal coverage, exhibits all the major properties of photoemission from Ag 4d bulk band. The electronic structure of all Ag films of up-to 1ML thickness is characterized by two intense 4d features that are explained in terms of spin orbit split d-quantum well states. The splitting of 0.25 eV in the Gamma point of the surface Brillouin zone was found to be constant in this coverage range. The experimentally determined band structure of the 1ML Ag film along the Gamma-M direction in the surface Brillouin zone is compared with DFT calculations. Starting from an unsupported Ag monolayer and taking into account the electronic structure of the Ni(111), the possible hybridization effects are discussed. Temperature dependence of the two d-QWS for 1ML Ag film, revealed their electron– phonon coupling constant. STM experiments showed that the outcome of Ag growth on Ni(111) are Moiré structured Ag fcc layers. Structural and electronic properties of Ag/Ni(111) were correlated to the Ag/Pd(111) and Ag/Cu(100) where Ag films are also of fcc structure.

Angle resolved photoemission spectroscopy has been proven as a reliable tool for the investigation of state specific electron phonon (e-ph) coupling parameter in quasi two-dimensional systems. The high energy and k-resolved photoemission spectrometers directly measures the photo-hole spectral function. In this way the slight temperature induced changes of the peak width can be correlated to the electron-phonon coupling constant. Investigation of s-p derived quantum well states (QWS) in ultra thin silver films showed significant enhancement of e-ph coupling parameter at small thicknesses , which is followed by its oscillatory behavior with increasing number of layers . There is, however, a very limited information on the e-ph coupling in QW systems of the states of d-character . We have studied e-ph coupling in 4d quantum well states (QWS) formed in one monolayer (ML) silver films grown on different low index surfaces: Cu(100), Mo(110), Ni(111), Pd(111). Structural analysis performed by LEED and STM shows that 1ML silver films on all surfaces are very similar having perfect or slightly distorted hexagonal structure. Electron phonon coupling constants were extracted from the linear fit of the temperature dependence of the photoemission peak widths. The measured variation of e-ph coupling constant across different substrate surfaces was correlated with the position of QW states with respect to the energy- and hybridization-band gaps of the substrates projected on the corresponding surfaces. This analysis provides the insight into the influence of the film-substrate interface on the strength of e-ph coupling parameter.

We investigated the resonant Auger process near the V 2p(3/2) edge in vanadium metal. Attention is centered on the onset of Auger decays and their behavior below the 2p(3/2) resonance. The 2p(3/2)3d3d decay has a crossover from the Raman-Auger to the normal Auger regime at the 2p ionization threshold. Meanwhile, Auger decays with core holes in the final state have normal Auger behavior even below the ionization threshold, the 2p(3/2)3p3p process being visible at 2.2 eV lower photon energy. The different resonant behavior of these Auger decays can be understood within the one-step model as final-state screening effects. affecting the photoexcitation.

According to results of the program “ Educational projects” , multidisciplinary team which led the program concluded that it is needed to take a lot of coordinated actions in order to encourage use of ICT in Croatian higher education system. The team recognized two main obstacles which can be cause for small number of university teachers who were using ICT in education process: lack of technical support for creation of educational materials and absence of procedure for valorisation of production of digital educational materials in the process of promotion of university teachers. In order to eliminate first obstacle CARNet established seven Referral centres for e-education which have been providing information and technical support for creation and application of digital materials in education process. After that, CARNet brought together another multidisciplinary team (mostly consisted of university teachers) with the goal to prepare a document which will (or could) be used by Croatian universities during categorisation, valorisation and evaluation of digital educational materials designed and prepared by their employees, university teachers. Beside, the document suggests how to describe, store, search and use digital educational materials with reference to creation of Croatian repository of digital educational materials. The paper will present the results of this project.

According to results of the program “ Educational projects” , multidisciplinary team which led the program concluded that it is needed to take a lot of coordinated actions in order to encourage use of ICT in Croatian higher education system. The team recognized two main obstacles which can be cause for small number of university teachers who were using ICT in education process: lack of technical support for creation of educational materials and absence of procedure for valorisation of production of digital educational materials in the process of promotion of university teachers. In order to eliminate first obstacle CARNet established seven Referral centres for e-education which have been providing information and technical support for creation and application of digital materials in education process. After that, CARNet brought together another multidisciplinary team (mostly consisted of university teachers) with the goal to prepare a document which will (or could) be used by Croatian universities during categorisation, valorisation and evaluation of digital educational materials designed and prepared by their employees, university teachers. Beside, the document suggests how to describe, store, search and use digital educational materials with reference to creation of Croatian repository of digital educational materials. This paper will present the results of this project.

One of the intriguing electronic phenomena in ultrathin films is the formation of so-called quantum well state s (QWS). Our research is focused to ultrathin silver films on V(100) in the limit of small thicknesses (1-5 layers). Due to the profound difference of the band structure of two metals, sp and d QWS are formed, dominating large parts of valence band region. We study the formation, structure and electronic structure of the system. Experiments were performed in three different ultrahigh vacuum systems: in Zagreb (STM, LEED, ARPES, AES), Bonn (STM, AES) and in Trieste at Elettra synchrotron (ARPES, LEED). The ab initio calculations were perfonned in the DFT approach, using DACAPO code.