Formation of linear structures of Sr and Gd films on the Mo(112) and W(112) surfaces

Fermi surface of Mo(112) and indirect interaction between adsorbed atoms

“…In the Monte Carlo simulations of the adsorbed layers within the lattice gas model, dynamical equilibration of a surface adlayer structure is achieved by moving randomly chosen particles to neighboring sites along the furrows [39,41,50,67,68]. The probability of each replacement (one "jump")…”

“…While the period along this quasi-one-dimensional (linear) adsorbate chains formed on Mo(112) is dictated by the lattice constant of Mo(112) along the <110 > direction (4.45 Å), the distances between the chains in these structures correspond to m periods of the lattice constant of the furrows (m × 2.73 Å). The formation of these quasi-one-dimensional atomic chains oriented perpendicular to the furrows, in spite of the interfacial dipole-dipole repulsion 2μ 2 /r 3 [24,[46][47] induced by the presence of adatoms at interatomic pair distance r, implies the existence of an oscillatory indirect interaction, which results in the minima of the effective potential at interatomic distances adopted by the adatoms in the direction along the furrows [24,39,41,43,[48][49][50][51][52][53]. Such indirect interaction stems from the Friedel oscillations [54] of electronic density of the substrate, formed for screening the charged adatoms, with the wavelength of π/k F and related indirect lateral interaction potential given by V ind (r) ~ сos(2k F r + δ)/r n [24,39,41,43,[48][49][50][51][52][53][54][55].…”

Changes in electronic structure through a disorder transition in gadolinium adlayers on W(112)

“…In the case of Hg on Ag(1 0 0), the adlayer substrate interaction is quite weak [4,5], but in the case of Pb on Ge(1 1 1), surface charge density waves may play a key role [6][7][8][9][10][11]. Lateral interactions mediated by the substrate (indirect interaction) are also evident in many metal on metal adsorption systems at low coverages [12][13][14][15][16][17]. The furrowed surfaces of the high melting point metals turn out to be one of the more suitable substrates for studies of this type of "through" substrate interactions [12][13][14][15][16].…”

“…Lateral interactions mediated by the substrate (indirect interaction) are also evident in many metal on metal adsorption systems at low coverages [12][13][14][15][16][17]. The furrowed surfaces of the high melting point metals turn out to be one of the more suitable substrates for studies of this type of "through" substrate interactions [12][13][14][15][16]. At issue is the question if the interaction is weakly mediated by the substrate, should the density of states of the overlayer be significantly affected by disorder, if local order and reversibility of the order/disorder transition is preserved?…”

“…Gd [14][15][16] in the submonolayer regime, on the furrowed surface of W(1 1 2) and Mo(1 1 2), are a consequence of a competition between long-and short-range forces, leading to the adlayer chainlike p(1 × 7) structure and c(2 × 2) structure, as indicated in Fig. 1, formed at the coverages of 0.14 and 0.5, respectively, defining coverage here by ϑ = n Gd /n W (the ratio of the surface concentration of the Gd adatoms n Gd and surface W(1 1 2) atoms n W ).…”