Production of Hydronium Ion (HO) and Protonated Water Clusters (HO)H after Energetic Ion Bombardment of Water Ice in Astrophysical Environments.

Water ice exists on many objects in space. The most abundant icy species, among them water, are present in the icy satellites of the outer Solar System giant planets. The nuclei of comets, which are mainly composed of water ice, give another example of its abundance.

Mid-IR band strength, density, refractive index, and thermal evolution study for solid CHDOH pure and in astrophysical relevant mixtures.

We present a novel experimental study on solid CHDOH pure and in astrophysical relevant mixtures. Solid samples were accreted under ultra high vacuum conditions at 17 K and were analyzed by mid-infrared transmission spectroscopy. Refractive index, density, and mid-IR band strength values were measured for pure solid CHDOH.

Two-color surface plasmon resonance nanosizer for gold nanoparticles.

We study the potentialities of a two-color Surface Plasmon Resonance (SPR) spectroscopy nanosizer by monitoring the assembling of a colloidal dispersion of citrate stabilized gold nanoparticles (AuNPs) on SiO surface. When the AuNPs/water composite's optical density layer is negligible and the electron mean-free path limitation is taken into account in the AuNPs' dielectric constant;s formulation, the surface density σ of the nanoparticle array and the statistical mean size of the nanoparticles can be straightly determined by using two-color SPR spectroscopy in the context of Maxwell's Garnett theory. The optical method, demonstrated experimentally for AuNPs with a nominal mean diameter of 15 nm, can, theoretically, be extended to bigger nanoparticles, based on a simple scaling relation between the extinction cross section of the single nanoparticle σ and the surface density σ.

Ozone and carbon trioxide synthesis by low energy ion implantation onto solid carbon dioxide and implications to astrochemistry.

Ion implantation experiments were carried out on amorphous (30 K) and crystalline (80 K) solid CO2 using both reactive (D(+), H(+)) and non-reactive (He(+)) ions, simulating different irradiation environments on satellite and dust grain surfaces. Such ion irradiation synthesized several new species in the ice including ozone (O3), carbon trioxide (CO3), and carbon monoxide (CO) the main dissociation product of carbon dioxide. The yield of these products was found to be strongly dependent upon the ion used for irradiation and the sample temperature.

Novel measurements of refractive index, density and mid-infrared integrated band strengths for solid O(2), N(2)O and NO(2):N(2)O(4) mixtures.

We present novel measurements of the refractive index, density and integrated band strengths of mid-infrared features of solid N(2)O at 16K and of NO(2) and N(2)O(4) in two frozen NO(2):N(2)O(4) mixtures deposited at 16 and 60K. The refractive index and density measurements were performed also for frozen O(2) deposited at 16K. In this case, the integrated band strength values could not be determined since O(2) is a homonuclear molecule and therefore its fundamental mode is not infrared active.