Postdoc's poster chosen for oral presentation

Eric Schelter had his poster selected for oral presentation at a Gordon Research Conference on Inorganic Chemistry in Newport, R.I. Being selected was an honor in itself because only four of 120 posters submitted were chosen for oral presentation. On top of that, Schelter was the only postdoc; the other three presenters were assistant professors up for tenure.

“It was a real thrill to stand up and talk in front of the demigods of inorganic chemistry,” Schelter said.

Schelter received a doctorate in inorganic chemistry from Texas A&M University in 2004. He is in his second year of a Seaborg Institute postdoctoral appointment in Actinide, Catalysis, and Separations Chemistry (C-SIC) under the mentorship of Jaqueline Kiplinger.

“Eric did a superb job,” said Kiplinger. “Lots of people were really impressed and commented accordingly.”

Schelter’s poster was titled “Covalency and Magnetic Communications in 5f-Element Complexes.” Co-authors include Kiplinger, fellow postdoc Jacqueline Veauthier, student Kimberly Jantunen, Brian Scott, David Morris, Joe Thompson, and Kevin John, all of whom are members of Los Alamos’ Chemistry or Materials Science Divisions.

The research focuses on how 5f orbitals in actinide ions may be involved in metal-ligand bonding, if involvement of these orbitals affects the properties of complexes of these ions, and if multimetallic complexes will exhibit metal-metal communication. The penultimate result was exciting, according to Schelter, and revealed a completely novel structure type: the fi rst heterometallic 4f-5f complex. The complex serves as a discrete molecular unit that can be studied to detect short-range electronic and magnetic interactions in f-element complexes.

For this study, the researchers began by synthesizing eight uranium complexes with slightly different structures and examining them to see what was happening between the uranium ion and ketimide ligands. The researchers found that there was a strong interaction between the uranium ion and the ligand in these complexes, which indicated a good electronic and magnetic pathway for communication.

Next, by hooking two metal ions together, in this case uranium and ytterbium, the complex was found to exhibit magnetic coupling, the fi rst actinide–lanthanide compound to do so. Current research uses compounds containing one actinide and two lanthanide ions, but eventually the study will use multiple actinides. Lanthanides are being used as “stepping-stone” complexes because their electronic structures are relatively more simple than those of the actinides.

Schelter says the system the researchers have developed makes for interesting study because the lanthanide site on this molecule can be substituted with any lanthanide ion, which allows the researchers to expand their study and try a lot of different things.

The Gordon Conferences focus on new, unpublished research. Schelter is in the process of writing three papers based on the content of the poster. The research is one aspect of a Laboratory Directed Research and Development project in collaboration with Theoretical and Materials Science and Technology Divisions.

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