Two types of anion states are shown to coexist in nanometer-scale polyacene cluster anions. Naphthalene and anthracene nanoclusters having a single excess electron were produced in the gas-phase. Photoelectron spectra of size-selected cluster anions containing 2 to 100 molecules revealed that rigid "crystal-like" cluster anions emerge, greater than approximately 2 nanometers in size, and coexist with the "disordered" cluster anion in which the surrounding neutral molecules are reorganizing around the charge core. These two anion states appear to be correlated to negative polaronic states formed in the corresponding crystals.

Anion photoelectron spectroscopy of acetonitrile cluster anions, (CH3CN)(-)(n) (n=10-100), successfully demonstrates the competitive coexistence of two different anionic species: a solvated electron and a solvent-bound valence anion. The distinctly different nature of these anions is revealed by hole-burning-type photoelectron spectroscopy and relative photodetachment cross section measurements. This unusual coexistence is attributed to the closely lying nature of their anionic states at just the number of solvent molecules sufficient to almost complete the first solvation layer.

Ion-mobility mass spectrometry is used for measuring single-charged sodium cation (Na + ) adducted polyethylene glycol (PEG) and polypropylene glycol (PPG). The collision cross sections of PEG and PPG are measured in dependence of the number of monomer units per chain, which can directly be related to the value of chain stiffness, i.e., the characteristic ratio (C n ). The evaluation of the data according to the globule model, which assumes that the chain in the gas phase exhibits spherical dimensions, yields very good agreement with the literatureknown reference values and C n of 3.96 and 5.76 for PEG and PPG, respectively, is obtained. The presented method, for which practical guidelines are also presented, is extremely quick and easy to perform and provides stunningly rapid access to the conformation data of synthetic polymers.

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Ion‐mobility mass spectrometry of doubly charged polyethylene glycol (PEG) is performed after electrospray‐ionization time‐of‐flight mass spectrometry and the dependency of the effective collision cross‐section, CCSeff, on the number of monomer units, n, is evaluated with the help of molecular dynamics simulations. Assuming a balance between elastic and Coulomb forces inside short and asymmetric doubly charged chains, a method is developed for evaluating the dielectric constant, ε, which is found to be 7.87 for PEG for n = 14–28. From the same experiment at higher chain lengths, the characteristic ratio Cn of 4.30 for PEG (n ≥ 63) can be evaluated according to an earlier reported method, which is demonstrated here to also work with doubly charged species. The proposed method enables an extremely swift and precise measurement both of ε and Cn of polymer that is free of solvent or impurities from one single experiment.