Assessment of the Second-Ionization Potential of Lawrencium: Investigating the End of the Actinide Series with a One-Atom-at-a-Time Gas-Phase Ion Chemistry Technique.

Experiments were performed at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron facility to investigate the electron-transfer reduction reaction of dipositive Lr ( = 103) with O gas. Ions of Lr were produced in the fusion-evaporation reaction Bi(Ca,2n) Lr and were studied with a novel gas-phase ion chemistry technique. The produced Lr ions were trapped and O gas was introduced, such that the charge-exchange reaction to reduce Lr to Lr was observed and the reaction rate constant was determined to be = 1.

Infrared emission following photolysis of methylisothiocyanate and methylthiocyanate.

Methylisothiocyanate (CH(3)NCS) was photolyzed at 193 and 248 nm, and the resulting time-resolved infrared emission was observed. Similar experiments were performed on methylthiocyanate (CH(3)SCN) photolyzed at 193 nm. Previous work suggested that these isomers undergo excited-state isomerization prior to dissociation, but other experiments have contradicted this claim.