6415of the most highly charged myoglobin charge states (observed for the AMP studies). While the reduced intensities of the higher charge states may simply reflect a shift in the entire distribution to lower charge state, the high attenuation rat@ lead us to believe that ion-neutral processes may also contribute. Indeed, studies by McLuckey et ai. have shown that ion-molecule reactions can preferentially attenuate higher charge states." It is believed that Coulombic forces result in the higher charge states being more reactive. Uncertainties in the reaction rates and thermodynamics of their reactions presently preclude unambiguous interpretation of our results.We believe that under our conditions, reaction with multiply protonated macroions could be a requirement for detectable charge inversion of singly charged anions (see Table I). A "one-step" multiproton transfer (reaction 1) could have substantially largerrates than a two-step sequential charge inversion (Le., an ion-ion reaction followed by an ion-molecule reaction). Although the first neutralization step is likely also to occur, we believe it is unlikely to contribute to the charge inversion process due to a rate-limiting reionization step. One might also expect the ionneutral process would have a collision cross section substantially lower than that of the initial ion-ion step. A single-step charge inversion process would explain both the high effciency for overall inversion and the requirement for multiple protonation of the positive ion reactant.The evidence presented for charge inversion in the reaction of singly charged anions with multiply charged macroions raises many questions for future ion-molecule and ion-ion reaction studies. We wonder about the roles of ion structure, energetics, and chemical equilibrium on these reactions. If we assume that the charge inversion occurs as a result of a single ion-ion encounter (reaction l), how rapidly do the two protons transfer and how might that transfer be influenced by the chemical nature and proximity of the charge sites? What role, if any, is played by associated solvent molecules and the bath gas? Further investigations are being initiated to address these issues.Nascent vibrational skate distributions of SO(X3Z-) have been measured by laser-induced fluorescence spectroscopy following the 193-nm photodissociations of SO,, SOCI,, and (CH3),S0 in the gas phase. All three of the distributions are found to be inverted, indicating strong dynamical effects in the photodissociation processes. A Franck-Condon/golden rule model is used to propose mechanisms to account for the experimental vibrational distributions.

An atom-economic synthetic method is developed to access CPP materials used for photocatalytic H2 production from H2O, and the PHP reaction can be greatly accelerated by DMF cosolvent, leading to an HER of 15 975 μmol g−1 h−1 without the aid of Pt.

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