Probing the structure of gas-phase metallic clusters via ligation energetics: sequential addition of C2H4 to Agm+ (m=3-7).

A new method that utilizes ligation to probe geometries of clusters in the gas-phase has been developed. This technique bases structural assignments on thermodynamic quantities obtained for sequential ligand additions to a bare cluster. The information is obtained from temperature-dependent equilibrium data.

Conformation and luminescence of isolated molecular semiconductor molecules.

In this article, we describe, for the first time, direct comparisons of the detailed structures of two small molecule organic semiconductors, oligo(phenylenvinylene) (OPV) molecules with chains of five and six phenyl rings (5R-OC(8)H(17) and 6R-OC(8)H(17)), respectively, and their luminescence properties on a single molecule level. Our data originate from a combination of two powerful diagnostic tools in physical chemistry: ion mobility and single molecule fluorescence spectroscopy. These techniques enable us to precisely determine the shapes of isolated molecules in the gas phase and to correlate these structures to the emission from single molecules supported on bare glass substrates.

On the dissolution processes of Na2I+ and Na3I2+ with the association of water molecules: mechanistic and energetic details.

The sequential association energies for one through six water molecules clustering to Na(2)I(+), as well as one and two water molecules clustering to Na(3)I(2)(+), are measured. The association energies show a pairwise behavior, indicating a symmetric association of water molecules to the linear Na(2)I(+) and Na(3)I(2)(+) ions. This pairwise behavior is well reproduced by Density Functional Theory (DFT) calculations.