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This research project set out to shed light at the ammoniated electron by investigating the electron binding motifs of excess electrons attached to ammonia clusters and ammonia nano-droplets. Over the last funding period the first part of the ammonia project was completed, the investigation of small clusters with ab initio methods. Research focusing on ab initio calculations for larger clusters and on model building is in progress. Moreover, a second major project was started owing to my observation that the originally proposed project was less suitable for undergraduate researchers than anticipated. This second project deals with the reactivity of N-oxime ethers (N-oxime ether project), and is a collaboration with a local organic chemist (Dr. Debra Dolliver).

At the start of the funding period practically nothing was known about small ammonia cluster anions. The smallest species observed experimentally was the 35-mer, however, the size of the smallest detected cluster was pushed down to the 13-mer by the Ahmed Zewail's group in early 2008. Theoretically small ammonia cluster anions had only been studied as models for solvent cages, and only artificial arrangements had been considered. The first step of the current project was to identify isomers, or at least conformations, of small ammonia clusters that do bind excess electrons. While the smallest cluster possible, the ammonia dimer, does have conformers that do bind an electron, its structure is too flexible to allow the formation of long-lived anions. In contrast, the trimer and the tetramer are predicted to have long-lived anions, and these species have been characterized through ab initio calculations, and the results have been published. The same study also considered a model solvent cage of six ammonia molecules, and the analysis of the ab initio electron density clearly refutes the density-functional based notion that an ammoniated electron could have a strong “delocalized radical anion” character.

The second step of the ammonia project involves model building, and model feedback into ab initio calculations for selected structures of larger cluster anions. The envisioned models consist of an ammonia-ammonia potential coupled with an electron-ammonia potential, the ammonia monomers are treated classically, the excess electron is treated as a quantum particle. The original plan to develop first a new ammonia-ammonia potential turned out to be unnecessary, since a new potential including many-body polarization effects was published in early 2008 by Massimo Mella's group. This potential was implemented into a new computer code and coupled with a parallel-tempering Monte-Carlo algorithm. It is currently used in conjunction with an electric-field bias to search for ammonia clusters with large dipole moments in the six to ten monomer range.

The second major project, the N-oxime ether project, was started when it became clear that the undergraduate student working with me was overwhelmed with the ammonia project. At that time a colleague had a project that needed theoretical input, which allowed my student to switch projects. The new project turned out to be far more suitable for an undergraduate researcher as (1) my student could use standard software with a graphical user interface, and consequently felt much more in control of her work, and (2) her peers worked in the experimental group interested in her results which provided a very strong motivation. Scientifically this project dealt with the mechanism of two competing reactions N-oxime ether azides undergo. My student contributed significantly to gaining an understanding of the two competing reaction mechanisms and of the reaction conditions that favor either pathway. At this time a joint paper of Dr. Dolliver, myself, and three of our research students has been accepted for publication in the Journal of Physical Organic Chemistry.

In addition to the scientific results as such, the grant has , and has had, further beneficial impacts my carrier. Because of it I could start an ambitious independent research program instead of dabbling with toy problems aimed primarily at providing a research experience for students. By these means I shall be able to establish a track record of performing high quality research at an undergraduate institution, that is, to show that even though my paper-production-frequency will be smaller than that of research university professors, my research itself can be held to the same standards as the work done at research universities. The same is true for my students. It makes a big difference to them to know that they are participating in work that will at some point be published in a proper research journal, and to present posters at meetings researchers from major institutions are interested in.