Carl’s MSPIRE research has involved the use of the free electron laser for infrared experiments (FELIX) facility at FOM ”Rijnhuizen” to measure infrared multiple photon dissociation (IRMPD) action spectra of alkali metallated complexes of methionine, one of the two amino acids containing a sulfur side chain. Spectra were obtained for M⁺(Met) where M⁺ = H⁺, Li⁺, Na⁺, K⁺, Rb⁺, and Cs⁺. Combined with accurate quantum chemical calculations on these systems, the results indicate that the heavier metals exhibit multiple conformers, whereas the lighter metals have only a tridentate configuration. He also participated in the study at FELIX of the structures of the crown ethers (12crown4, 15crown5, and 18crown6 ) complexed to Zn²⁺ and Cd²⁺.

In his Ph.D. studies, Carl examined the interactions of water with alkali earth metal dications, measuring the inner shell hydration energies for Mg²⁺, Ca2⁺, and Sr²⁺ for the first time. This was achieved using threshold collision induced dissociation (TCID) in a guided ion beam tandem mass spectrometer fitted with a new electrospray ionization source. Such studies were facilitated by his development of an in-source fragmentation technique for the production of thermalized ions in the electrospray source.

Carl received his Ph.D. in chemistry from the University of Utah in 2009. He is currently working at Heritage Environmental Services, Indianapolis, IN.

Figure. The spectrum of Li⁺(Met) complex can be completely reproduced by the spectrum calculated for the tridentate structure shown in the upper left. As the metal ion gets heavier, new bands in the spectra grow in, indicating the presence of other structures, primarily those where the metal cation binds to both oxygens of the carboxylic acid group in both charge solvated and zwitterionic conformations.