THERMAL-ISOMERIZATION IN ISOLATED CESIUM-HALIDE CLUSTERS

We have used photoelectron spectroscopy to observe thermal isomerizati on in cesium-halide cluster. anions. In many of the (CsX)(n)Cs-m(-) (X = Cl,Br,I; n = 2-7; m = 0, 1) systems we have studied, small changes' in the source nozzle temperature produce dramatic changes in the dist ribution of cluster isomers. When specific isomers are selectively pho todepleted, isomer interconversion quickly reestablishes the thermal i somer distribution; even though the clusters are isolated in a cluster beam.