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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].

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.

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.

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Due to real space anisotropy of the vicinal Si(111) surfaces, hot electrons can be expected to exhibit different dynamics along and perpendicular to the steps as compare to the Si(111) flat surface. We made a comparative study of Pb overlayer structures grown on vicinal Si (557) and flat Si (111) using femtosecond time- and angle- resolved two-photon photoemission. We mapped the unoccupied electronic band structure near Γ and find that both systems have two unoccupied states at E−EF=3.3 and 3.5 eV. In pump-probe experiments combined with a position sensitive electron time of flight spectrometer we analyze the ultrafast momentum dependent electron dynamics along two in plane directions. On vicinal surfaces we observe a specific, momentum dependent population dynamics which are absent on the flat surface. This signature shows a delay in population build up of 5 fs as a function of angle with respect to the terrace direction. We assign this behavior to step-induced scattering. We gratefully acknowledge funding by the DFG through FOR1700.

The electron dynamics at a metal-molecule interface is studied with time-resolved two-photon photoemission. We report here energies, workfunction changes and lifetimes of excited electronic states in amorphous D2O/Cu(111) and coadsorbed C6H5F systems after optical excitation with 3.8 eV + 1.9 eV femtosecond laser pulses. We observe a decrease in lifetime of the solvated electron state from 90±5 fs for bare D2O to 60±5 fs for coadsorbed C6H5F. Further, after a total estimated exposure to 0.5×106 photons per C6H5F molecule, a workfunction change of 200±50 meV was observed. Due to the absence of photo-induced workfunction changes in the single stack D2O/Cu(111) and C6H5F/Cu(111), this change is concluded to be mediated by solvated electrons. Additional experiments on C6H5Cl/D2O/Cu(111) were performed and an even larger photoinduced workfunction change was observed. The increase in workfunction is explained by the formation of F−/Cl− as a photo-chemical dissociation product. We conclude to have identified the charge transfer to C6H5F(/Cl) and a fingerprint of its photoinduced dissociation. Future experiments aim to systematically change the UV photon energy and the molecule acceptor level.

Quasi-1D materials are expected to exhibit exotic properties that are considerably different from those of their corresponding bulk material counterparts. As a consequence of the strong real-space anisotropy of these systems, significant differences in, e.g., electron scattering rates along and perpendicular to the wire structure can be expected. We investigate this particular aspect using time- and angle-resolved two photon photoemission from the Pb/Si(557) nanowire system. We present results regarding the unoccupied electronic structure and ultrafast relaxation of optically excited carriers probed as a function of two mutually independent in-plane momentum directions along and perpendicular to the nanowire orientation. We gratefully acknowledge funding by the DFG through FOR1700.

Very good candidates to study the exotic physics of quasi 1D systems are self-assembled atomic wires. Particularly attractive are metallic wires adsorbed on semiconducting surfaces which are not only geometrically strongly anisotropic, but also exhibit quasi-1D Fermi surfaces. In metallic wires, rather strong correlation effects are expected due to the reduction of electrostatic screening. However, the correlations are modified in quasi-1D electron systems owing to the coupling to the environment. Interactions wire to wire and wire to substrate should also manifest themselves in the electronic structure and in an anisotropic electronic interaction and relaxation dynamics after photoexcitation. As a prototypical system we studied the Pb/Si(557) nanowire system with the intention to explore the impact of structural and electronic band anisotropy to the ultrafast hot electron decay dynamics. To investigate elementary and microscopic interactions responsible for the population decay of optically excited electrons as a function of electron momentum we used femtosecond time- and angle-resolved two photon photoemission spectroscopy (2PPE). Two bands in the unoccupied electronic band structure are identified for which the dynamics in various points of the in-plane k-space was studied. We find indications of a momentum dependent population probability, but at present the band structure effects cannot be excluded. As already reported, the electrical conductivity in the system switches from 2D to 1D behaviour upon crossing the critical temperature due to the temperature dependent structural transition. This structural instability opens the opportunity to study different aspects, for example temperaturedependent dynamics or the optically driven insulator-metal transition in the future.

Strongly anisotropic systems, like, e.g., metallic nanowire arrays grown on semiconducting surfaces, are expected to exhibit significantly different electronic dispersion - along and perpendicular to the wire structure. Angle-resolved photoemission is an excellent tool to study electronic band dispersion, but is often limited to (i) one momentum direction in a single measurement and (ii) the occupied electronic structure. Here, we report on femtosecond-laser based two-photon photoemission experiments on Pb/Si(557) nanowires that map the unoccupied electronic structure. Using a position-sensitive time-of flight spectrometer, the dispersion along and perpendicular to the wires can be analyzed simultaneously in a single measurement. Furthermore, by delaying two light pulses with respect to each other, the lifetimes of these unoccupied electronic states can be measured in a pump-probe experiment. We present first time- and momentum-resolved studies on the unoccupied states in this system. We gratefully acknowledge funding by the DFG through FOR1700.

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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.

One of the most remarkable aspects in the study of surfaces is that their properties can be extremely different from those of the corresponding bulk material. The broken symmetry at the surfaces is reflected on electronic properties. For example, electron can be trapped between two barriers: image potential barrier introduced by surface, and a gap in the projection of bulk electronic on the particular surface, resulting in 2D surface states. Also on some surfaces surface reconstruction may take a place. In addition to this, the relative importance of the surfaces increases for smaller structures. This is particularly relevant for nano-technology where surfaces are often used as templates for assembling nano objects. There is a great variety of surface experimental techniques giving information about: atomic structure, electronic structure, thermal excitations, chemical composition, adsorption and desorption phenomena.

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.

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.

Istraživana su strukturna i elektronska svojstva adsorbiranih metalnih nanosistema. Kao modelni nanosistemi odabrani su ultra tanki filmovi srebra na Pd(111), Ni(111) i Cu (100). Filmovi su pripremljeni naparavanjem u uvjetima ultra visokog vakuuma. Upotrebom fotoemisijske spektroskopije praćen je razvoj valentne vrpce u ultra tankim filmovima srebra. Posebna je pažnja usmjerena na dio te vrpce koji se nalazi u energijskom području procijepa volumnih vrpci podloge projiciranih na površinu. U navedenom području opažena su stanja kvantne jame u svakom od istraživanih sistema. Strukturna svojstva su istraživana površinski osjetljivim tehnikama LEED i STM. Ona pokazuju da iako je strukturno uređenje slojeva srebra fcc struktura, postoje razlike izražene u stupnju distorzije, kao i u detaljima atomskog uređenja. Ag/Pd(111): Strukturna istraživanja Ag/Pd(111) sistema su pokazala da se monosloj srebra formira pseudomorfnim rastom na Pd(111) podlozi, zadržavajući fcc (111) heksagonalnu strukturu. Rast započinje formiranjem otoka uz rubove stepenica. Sa povećanjem adsorbiranog srebra povećavaju se lateralne dimenzije otoka, koji se zatim spajaju. Nakon saturacije prvog sloja započinje rast drugog sloja. Treći sloj počinje rasti kada je drugi gotovo sasvim popunjen. Rezultat su dobro uređeni homogeni slojevi srebra za prvi i drugi monosloj. Usporedba fotoemisijskih spektara i DFT računa za 1 i 2 ML Ag duž smjera visoke simetrije pokazala je dobro slaganje u disperziji pojedinih opaženih d vrpci. Slaganje je dobro i za vezivne energije ukoliko se uzme u obzir da DFT računi daju Ag 4d vrpce pomaknute za približno 1 eV prema Fermi nivou u odnosu na vrpce u spektrima. Na osnovu izostanka bilo kakve ovisnosti energijskog položaja fotoemisijskih maksimuma o pobudnoj energiji (21.2 eV i 16.8 eV), njihovog položaja unutar energijskog procijepa projiciranih volumnih vrpci paladija na (111) površinu, te DFT računa, opažena stanja u području Ag 4d vrpce opisujemo kao stanja kvantne jame. U fotoemisijskim spektrima za 1 ML opažamo dva maksimuma koja smo pripisali fotoemisiji iz dvije Ag vrpce čije su simetrije dxz i dyz. Razdvajanje vrpci u točki površinske Brillouinove zone koje iznosi 0.27 eV objašnjavamo učinkom spin-orbit interakcije i kristalnog polja. Ag/Ni(111): LEED i STM istraživanja Ag/Ni(111) sistema su pokazala da srebro na Ni(111) podlozi raste tako da su međuatomske udaljenosti jednake onima na Ag(111) površini. Zbog velikih razlika u konstantama rešetki od 16%, kao rezultat ovakvog načina rasta nalazimo Moiré strukturu. Kao i za Ag/Pd(111) sistem, STM eksperimenti su pokazali da rast srebra započinje formiranjem otoka čije se lateralne dimenzije povećavaju sa daljnjom adsorpcijom srebra, sve do popunjenja monosloja. U ovom sistemu (nakon popunjenja prvog sloja) drugi i treći sloj rastu istovremeno. Fotoemisijska istraživanja (za različiti broj atomskih slojeva srebra) ukazuju na nastanak stanja kvantne jame d simetrije unutar energijskog područja projiciranih volumnih vrpci nikla na (111) površinu. Energijski procijep u centru površinske Brillouinove zone se proteže od 2.5 eV do 4.8 eV vezivne energije. Kao i u fotoemisijskim spektrima za 1 ML Ag/Pd(111) opazili smo dva maksimuma koja pripisujemo fotoemisiji iz vrpci dxz i dyz simetrije. Razdvajanje maksimuma u točki površinske Brillouinove zone iznosi 0.25 eV. Ag/Cu(100): U provedenim STM i LEED eksperimentima Ag/Cu(100) sistema nalazimo da se rast srebra do popunjenja prvog sloja odvija na potpuno drugačiji način nego na Pd(111) i Ni(111). Za manje od 0.13 ML Ag, nastaje neuređena struktura u kojoj Ag atomi supstituiraju pojedine atome Cu(100) površinske rešetke. Za više od 0.13 ML započinje izdvajanje Ag atoma iz Cu matrice i njihovo nakupljanje u izdužene strukture u kojima nalazimo c(10x2) superstrukturno uređenje. Nakon popunjenja prvog sloja, drugi sloj započinje rasti u otocima, u kojima također opažamo superstrukturno c(10x2) uređenje. Na popunjenom drugom sloju dalje rastu 3D otoci. Energijski procijep u projiciranim volumnim vrpcama bakra na (100) površinu proteže se od 4.6 eV do 5.1 eV vezivne energije. U ovom energijskom području fotoemisijska istraživanja također ukazuju na nastanak stanja kvantne jame. Kao i u Ag/Pd(111) i Ag/Ni(111) dva maksimuma u fotoemisijskim spektrima pripisujemo fotoemisiji iz vrpci dxz i dyz simetrije. U točki površinske zone oni su razdvojeni za 0.28 eV. Za sve studirane sisteme karakterističan je fotoemisijski spektar koji u području Ag 4d vrpce, već za pokrivenosti između 3 ML i 7 ML (ovisno o sistemu), poprima sve značajke karakteristične za fotoemisiju iz volumne vrpce. Na osnovu rezultata strukturnih istraživanja i istraživanja elektronske strukture, detalji u načinu rasta i strukturna svojstva filmova korelirani su sa elektronskim svojstvima. U slučaju Ag/Cu(100) strukturna promjena iz površinske slitine u potpuno izdvojeni Ag sloj praćena je promjenom razdvajanja dva fotoemisijska maksimuma (dxz i dyz). U točki ova se vrijednost mijenja od 0.22 eV do 0.28 eV (za 1ML). Promjena je dovedena u vezu sa povećanjem utjecaja kristalnog polja tijekom formiranja monosloja. U Ag/Pd(111) i Ag/Ni(111) sistemima energijski položaji dxz i dyz fotoemisijskih maksimuma se ne mijenjaju tijekom formiranja monosloja. Takvo ponašanje dovodimo u vezu s načinom rasta, odnosno činjenicom da koordinacijski broj Ag atoma (izuzev atoma na rubovima otoka) ostaje nepromijenjen tijekom formiranja monosloja. Utjecaj podloge na stanja različitih simetrija izvan centra Brillouinove zone razmatran je kroz moguće hibridizacijske efekte. Na osnovu razlika u ponašanju dviju opaženih vrpci u fotoemisijskim spektrima za 1 ML Ag sisteme, pojedinoj je vrpci pripisana dxz, odnosno dyz simetrija. Diskutirana je širina (FWHM) prvog d-stanja kvantne jame i iz temperaturne ovisnosti nađena je konstanta šupljina-fonon vezanja u Ag/Ni(111) sistemu.

We present a combined, experimental, and computational investigation of the growth mode and the valence-band structure of Ag/Pd(111), with the focus on the Ag 4d derived quantum well states. Low-energy electron diffraction and scanning-tunneling microscopy are used to determine epitaxial, layer-by-layer growth of silver on the palladium substrate. High-resolution (in both energy and angle) photoelectron spectra and ab initio density-functional band-structure calculations are compared for 1 and 2 ML silver films along the Gamma-M-' high symmetry line of the surface Brillouin zone. The observed d-derived electronic states and their dispersion are explained in terms of quantum well states. The interaction of the silver 4d electronic states with the palladium substrate is discussed.

The structural and electronical properties has been investigated by STM, LEED and ARUPS.