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Two different Sb-induced phases have been found upon annealing on freshly evaporated Si(1 0 0)2 × 1 surfaces. The surface electronic structures of the two phases (1 × 1-Sb and 2 × 1-Sb) have been studied with surface differential reflectivity (SDR) and angle-resolved photoelectron spectroscopy (ARUPS). Both techniques show the existence of a gap of approximately 1.6 and 1.4 eV for the two phases, with the empty state located near the Fermi level.

We have investigated the morphology, chemical bonds and electronic states of CVD carbon grown on silicon (111) substrates by means of scanning electron microscopy (SEM), Auger electron spectroscopy (AES), ultraviolet photoemission spectroscopy (UPS) and optical reflectivity. Both AES and UPS techniques show variations in the observed spectra if referred to samples at different stages of growth. The optical reflectivity technique has also been used in order to study the diamond-substrate interface and to quantify the film thickness.

A red figure calyx crater of uncertain attribution, found in the Celle necropolis of Falerii Veteres, and several other red figure vases coming from different Italic and Attic workshops were analysed in situ with X-ray fluorescence spectroscopy. The comparison of the concentrations of the minor elements present in the ceramic body, in particular Cr, Ni, Sr, seems to support the attribution of the vessel to an Athenian workshop.

We have an authentic object, an Etruscan clay painted urn, which so far is unique in the world, found in a tomb in Tarquinia and preserved in the Museum of Tarquinia, which dates around 500/490 BC. We have also one urn very similar to this, in Rome in the Gorga Collection, without provenance. To remove any doubt about the authenticity of this urn, we decided to use the thermoluminescence analysis. We also used the XRF. Moreover, the traces of cobalt highlighted with XRF in the hair of a male figure of the Gorga urna seems to indicate the use of modern paint; the traces of lead, perhaps a final polish color. With the analysis on object from archaeological known contexts (the urn from Tarquinia), we have been able to establish that the other urn is modern. The colors used in the urn of the Gorga Collection were based on manganese and cobalt and the clay shows a widespread presence of Cadmium.

Uncoated DNA molecules marked with an activated tris (1‐aziridinyl) phosphine oxide (TAPO) solution were deposited on gold substrates and imaged in air with the use of a high‐resolution scanning tunneling microscope (STM). Constant‐current and gap‐modulated STM images show a clear evidence of the helicity of the DNA structure; pitch periodicity ranges from 2.5 to 3.5 nm whereas the average diameter is 2.0 nm. Molecular structure within a single helix turn was also observed. TAPO molecules have been imaged alone and appear as a crystalline structure of rows of molecules with a side‐by‐side spacing of 0.3 nm.

We present a determination of the complex surface dielectric function (SDF) of the CdTe(110)1 × 1 surface obtained by using polarized surface differential reflectivity data ( ΔR R ) obtained for the light electric vector along the [110] and [001] directions, i.e. “parallel” and “perpendicular” to the natural chains of the unreconstructed (110) surface. In the energy range below 3.3 eV the imaginary part of the SDF (ϵ′') and ΔR R are very similar while above 3.3 eV they differ markedly because of the effect of bulk contribution. Three mainly isotropic structures are clearly visible in the ϵ′' spectra at the following photon energies: 2.7, 3.3 and 3.65 eV. The interpretation of such structures in terms of optical transitions between surface state bands as derived from direct and inverse photoemission is shown. Moreover, the effective number of electrons per atom participating in the optical transitions is calculated for energies up to 4.0 eV.

Angle-resolved photoelectron spectroscopy and surface differential reflectivity have been used to study the electronic structure of Si(100):Sb-1\ifmmode\times\else\texttimes\fi{}1 and Si(100):Sb-2\ifmmode\times\else\texttimes\fi{}1 surfaces. For both surfaces, one occupied surface-state band has been mapped along the [010] and [011] directions. Both surfaces show a semiconducting behavior with a gap of 1.6 eV for the 1\ifmmode\times\else\texttimes\fi{}1-Sb and 1.4 eV for the 2\ifmmode\times\else\texttimes\fi{}1-Sb surface. A minimum-energy position at the Fermi level is derived for the empty surface-state band. The results are also compared with those obtained for the clean Si(100)2\ifmmode\times\else\texttimes\fi{}1 surface.

We present surface differential reflectivity results on the polarization dependence of optical transitions and on the oxidation of InP(110) surfaces in the energy range between 2.0 and 4.0 eV. The surface dielectric function has been computed for light electric vector along [110] and [001] directions. Three well defined optical peaks have been detected at the following energies: 2.6 eV (light electric vector along [110] direction), 3.1 eV (unpolarized), and 3.5 eV (light electric vector along [001] direction). Absorption kinetics is analyzed by following the reflectivity variation between 1×102 and 2×106 L of molecular oxygen at three selected spectral energies. Several well defined steps of the oxidation process are clearly resolved and discussed in terms of disappearance of intrinsic surface states, creation of acceptor and donor defect states, growth of In2O3.

We present surface differential reflectivity (SDR) results on the polarization dependence of optical transitions and on the oxidation of InP(110) surfaces in the energy range between 2.0 and 4.0 eV. The surface dielectric function has been derived for the light electric vector along [110] and [001] directions. The data show two anisotropic peaks at 2.6 eV (excited with the light electric vector along the [110] direction) and 3.5 eV (excited with the light electric vector along the [001] direction) and an almost isotropic behaviour for the peak at 3.1 eV. Absorption kinetics is analyzed by following the reflectivity variation between 1 × 10 2 and 2 × 10 6 langmuirs of molecular oxygen at three selected spectral energies. Several well-defined steps of the oxidation process are clearly resolved and discussed in terms of disappearance of intrinsic surface states, creation of acceptor and donor defect states, and growth of In 2 O 3 .

We present a determination of surface dielectric functions (SDF) of Si(111)2×1, Ge(111)2×1, GaAs(110) and GaP(110) surfaces obtained using polarized surface differential reflectivity (SDR) technique.

The optical transitions at the InP(110) cleaved surface are studied by normal incidence surface differential reflectivity in the spectral range between 1.5 and 4.0 eV. A sharp absorption peak has been detected at 3.1 eV together with smaller transitions at 3.6 and 3.8 eV. A determination of the surface dielectric function has been performed.

Uncoated DNA molecules marked with an activated tris(l-aziridinyl) phosphine oxide (TAPO) solution were deposited on gold substrates and imaged in air with the use of a high-resolution scanning tunneling microscope (STM). Constant-current and gap-modulated STM images show clear evidence of the helicity of the DNA structure: pitch periodicity ranges from 25 to 35 angstroms, whereas the average diameter is 20 angstroms. Molecular structure within a single helix turn was also observed.

We present results on the polarization dependence of Surface Differential Reflectivity in GaP(1 1 0) and GaAs(GaAs(1 1 0) surfaces. GaP(1 1 0) shows a transition at 2.8 eV which is excited only with the light electric vector parallel to the [1 1 0] direction; for the optical transition above 3.0 eV there is not any marked polarization dependence. GaAs(1 1 0) shows optical transitions between 2.6 and 4.0 eV which have a weak dependence on light polarization.