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The ability of Captisol® (sulphobutylether-β-cyclodextrin, SBE-β-CD), to form inclusion complexes, both in solution and in the solid state, has been tested in order to improve some unfavorable chemical-physical characteristics, such as poor solubility in water, of a bioflavonoid, Coumestrol (Coum), well known for its anti-oxidant, anti-inflammatory, anti-fungal and anti-viral activity. In pure water, a phase-solubility study was carried out to evaluate the enhancement of the solubility of Coum and, therefore, the occurred complexation with the macrocycle. The stoichiometry and the stability constant of the SBE-β-CD/Coum complex were calculated with the phase solubility method and through the Job's plot. After that, the solid SBE-β-CD/Coum complex was prepared utilizing a kneading method. The spectral changes induced by complexation on characteristic vibrational band of Coum were complementary investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopy, putting into evidence the guest chemical groups involved in the “host-guest” interactions responsible of the formation and stabilization of the complex. Particular attention was paid to the C O and O H stretching vibrations, whose temperature-evolution respectively furnished the enthalpy changes associated to the binding of host and guest in solid phase and to the reorganization of the hydrogen bond scheme upon complexation. From the whole set of results, an inclusion geometry is also proposed.

In this work, we present a FT-IR absorbance investigation on prehistoric ceramics with the aim of characterizing the phase transformations that occur during the cooking processes. The measurements were performed on several potteries belonging to the Middle Bronze Age excavated in the Catania hinterland (Sicily, Southern Italy). Based on the macroscopic observation, the samples may be distinguished on coarse and fine ceramics, and the petrographic study showed a strongly heterogeneous structure and composition. The results were compared with the data obtained by means of X-ray diffraction (XRD) and with the microscopic qualitative observations of the birefringence of the groundmass. The whole set of the data showed a firing temperature in the 800–900 °C range. The simultaneous presence in several samples of calcite and clay minerals and of new-formed Ca-silicates should be indicative of a quite primitive technological firing process with strong temperature variation inside the kiln.

The aim of this study was the microscopic and mesoscopic characterisation of archaeological pottery findings addressed to the identification of the manufacturing techniques. The samples under study were “Ionian Cups” sherds, coming from Poira, an archaeological site in eastern Sicily (South-Italy). These cups represent a ceramic typology widely diffused in the Mediterranean Area in archaic age (VI–V century BC). The identification of the production sites of these materials, originally manufactured in Greek-Eastern area and then largely diffused in Magna Graecia, is still an open question. Here, the microscopic structural characterisation was obtained by Fourier Transform Infrared absorption (FT-IR) measurements, which permitted us to determine the mineralogical phases present in the artefacts. Furthermore, Small Angle Neutron Scattering (SANS) measurements permitted the characterisation of the size distribution and surface characteristics of the mesoscopic aggregates formed by the minerals.

In the present work, we report a polarized Raman study versus temperature of the complex O–H stretching vibrational band (3800–3000 cm −1 ) performed in a glass forming liquid, namely propylene-glycol (PG), with chemical formula given by H[OCH(CH 3 )CH 2 ]OH. The spectra were collected in bulk and confined state within a sol–gel controlled porous glass having highly interconnected 25 A diameter pores and characterized by a huge number of silanol groups (Si–OH), able to interact with PG molecules via hydrogen bond. The goal was to investigate how the hydrophilic nature of the surface influenced the molecular mobility of this hydrogen-bonded system, by monitoring intra- and inter-molecular host–host and host–guest interactions. The analysed O–H spectral region was decomposed into Gaussian symmetrical profiles, each of them associated to a well-defined aggregate, triggered by the presence of H-bond. Passing from the bulk state to the confined one, a clear change of the dynamical properties has been revealed and related to the interactions with the surface. The observed results were discussed on the basis of current models for associated liquids.

The modification, compared to the bulk state, of the dynamics of liquids in confined geometry has attracted considerable interest in scientific research, also because of the close connection with many relevant technological problems, such as the building of optical switches, membrane separation, catalysis and tertiary oil recovery. We report the preliminary results of an Incoherent Quasi Elastic Neutron Scattering (IQENS) investigation on propylene glycol (PG: H[OCH(CH 3 )CH 2 ]OH), a low molecular weight polymer, both in the bulk and in the confined state, in order to show the different dynamical behaviour of this system as a consequence of the presence of an interface. In particular PG was confined in 26 A pores of a porous sol–gel glass with unmodified and modified inner surface, trying to distinguish the different role played by hydrophobic and hydrophilic confinement on its diffusive motion. The data have been interpreted in the framework of the well known Volino–Dianoux model for confined diffusion, and compared with the most recent literature in this field.

The aim of the present work is the characterization of ceramics artefacts coming from Locri Epizephiri, in order to understand the area of production and the baking temperatures. The macroscopic investigation, performed from an archaeological and chronological point of view, permitted the classification of the studied samples into two different groups: the former was constituted of amphorae fragments used for transport, characterized by a mixture of medium-fine grain, and the latter was constituted of tiles fragments with a mixture of coarse grain. All the samples date back to a period between the V and the IV century bc and present similar mineralogical–compositional characteristics. The ceramic samples were analyzed by X-ray diffraction (XRD), X-ray fluorescence and Fourier transform infrared (FT-IR) spectroscopy. XRD spectroscopy allowed us to identify the present crystalline substances. In particular, both in the amphorae and in the tiles, the main mineral is quartz. Furthermore, larger quantities of calcite, hematite and illite are present in the amphorae rather than in the tiles, while a larger amount of K-feldspar is present in the tiles rather than in the amphorae, finally gehlenite is definitively absent in the tiles. The FT-IR investigation was performed both at low and high frequencies. From all the obtained results it was possible to conclude that the provenance area of the ceramics was the Calabro–Peloritano one. The compositional variations could be attributed to the presence of the different workshops in the same zone and to the existence of several quarries of clay materials.

In this work we report a preliminary study of Fourier transform infrared spectroscopy on normal and neoplastic human skin samples suffering from two kinds of cancer, namely epithelioma and basalioma. The analyzed skin samples have been drawn from different parts of the human body, after biopsies. By performing a complex band deconvolution due to the complexity of the tissue composition, the analysis within the considered frequency region (900–4000 cm−1) of the collected IR spectra, allowed us, first of all, to characterize the presence of the pathologies and to show clear different spectral features passing from the normal tissue to the malignant one in particular within the region (1500–2000 cm−1) typical of the lipid bands.

This paper deals with the analysis of the intramolecular dynamics of the isolated Sulfur molecule under the effect of a new intramolecular potential model with continuous first derivative and therefore well suited for molecular dynamics simulations. The potential parameters were fitted to reproduce the available experimental vibrational frequencies by means of Molecular Dynamics simulations. The formalism of the symmetrized autocorrelation functions of internal coordinates was used to analyze the Molecular Dynamics data.

The mode mixing in the first electronic state of phenol, known as Duschinsky effect, responsible for dissymmetry between absorption and emission spectra, reduction of vibrational wavenumbers in S1 and cross sequences, has been calculated by means of a vibronic coupling approach. Although the results reproduce qualitatively the observed trend, they also show that a more quantitative analysis requires more accurate starting force fields.

The vibronic activity revealed by the TPE spectrum of pyrimidine has been examined and calculated in detail through a set of semi-empirical calculations. The results confirm previous interpretations of the experimental data and contribute to assign the symmetry of the lowest excited singlet states. Moreover, the most active modes have been individuated and the mechanisms of vibronic borrowing have been compared in the case of one-photon and two-photon spectra.