Cluster size specific chemistry: deuterium atom pickup in Sr+ solvated by ammonia

We report on recent experimental evidence for deuterium atom pickup in metal ion–polar solvent clusters. Mass spectral analysis shows the existence of species that correspond to the empirical formula Sr+(ND3)nDx, where x is as large as 4 for clusters in the size range n=10–15. Photodissociation spectra of several of these clusters indicate that their structures are very different from the purely ammoniated analogs, Sr+(ND3)n. Based on deuterium scavenging data and absorption spectra, we propose the formation of SrD+ to account for one of the excess deuteriums, and the existence of solvated ND4 to account for additional deuterium atoms in the cluster.