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We determined the potential energy surface (PES) of the He–H2O complex by means of Coupled-Cluster, Møller–Plesset, and valence bond calculations. The main features of the different PES are discussed and compared to previous literature results. We determined the rotovibrational structure of the complex under the assumption that the water molecule rotates freely. Whatever the computational scheme, the complex is predicted to have a single bound vibrational state and three rotational excitations. [Copyright &y& Elsevier]

We present results of a stratigraphic and environmental geochemistry study of the eastern sector of the Volturno river basin (Italy) using stream sediment and floodplain drill core samples. The cores, dated back to 7,000 years B.P., have been used to evaluate background (baseline) values. Pb isotopic compositions and toxic metal abundances have been determined to discriminate natural versus anthropogenic sources. The Pb isotopic compositions of the stream sediments overlap the values of Pb in petrol. The results from both stream sediment and drill core samples plot along a mixing line between the field that characterizes the volcanic rocks outcropping in the area (the natural component) and the Pb isotopic composition of petrol used in western Europe. Results suggest a prevalent contribution of the natural component for the Pb in the drill core samples and a prevailing anthropogenic component for the Pb isotopic compositions in the active stream sediments samples. [ABSTRACT FROM AUTHOR]

Lithostratigraphic analysis, geologic and geomorphologic surveys, and radiocarbon dating were carried out to elucidate the evolution of the Bagnoli-Fuorigrotta depression. The origin of the feature, located at the outskirts of Naples and confined between the ridge of Posillipo and the Agnano volcanic centre, was triggered by the huge volcanic-tectonic collapse, subsequent to the Tufo Giallo Napoletano emplacement (12 ka BP), which caused the Phlegrean caldera. Since then, its evolution has been controlled by the recurrent volcanic and tectonic events which occurred throughout the Phlegrean Fields as well as by sea-level rise. In particular, the tephra ejected from the vents of the Agnano centre (from 11 to 3.7 ka BP) modelled the depression by aggrading its bottom and shifting the coastline seaward. At present, a short erosion scarp, locally resembling a ‘palaeofalaise’, separates the plain reach (Coroglio plain) of the depression from the marginal Bagnoli-Fuorigrotta terrace. The depression fill consists of subaerial tephra and marine deposits with intercalations of palaeosols and transitional alluvial and lacustrine-palustrine sediments. Such an assemblage supports the inference that the depression underwent a rather complicated evolution, characterized by an overall subsidence trend in part overshadowed by the counteracting uplifting and tephra input. At Coroglio plain, the sympathetic effects of subsidence and sea-level rise were effective in preserving (apart from a few lacustrine-palustrine phases) a marine environment up to historical times. The final evolution of the plain dates back some 1.8 ka BP and depended upon the deposition of a coastal barrier capable of maintaining scattered swampy areas on the land. Since then, the plain was only affected by subsidence, at a rate inconsistent with further marine ingressions but compatible with the persistence of marshy spots until the complete reclamation of the area was accomplished in the nineteenth century. [ABSTRACT FROM AUTHOR]