Student Abstracts: Chemistry at LBNL

Wet Synthesis of Transition Metal-Imidazolole Complexes. MARIO ORTEGA (Fresno City College, Fresno, CA 93662) DALE L. PERRY (Ernest Orlando Lawrence Berkley National Laboratory, Berkley, CA 94720) .
The world around us, including medicinal chemistry and electronics, is all intertwined, and new products are created through several scientific processes, one being synthesis. The process of creating new drugs, materials, and semiconductors relies on the reactions of two or more substances to create a more complex one. Understanding the importance of this concept and utilizing are what enable breakthroughs to be made in many of these fields. During my time at LBNL, various metal-imidazole compounds were synthesized by me, all work being performed in a wet chemistry lab as well as an x-ray diffraction facility. The two highlighted chemical systems of my term here were cobalt imidazolate and copper imidazolate; both were created and crystallized utilizing the same process. Previous attempts at producing these complexes as high quality crystals were fruitless. The complex crystals were obtained from the parent compounds by careful adjustment of the reaction conditions. This process produced metal-imidazolate and metal-imidazole complex crystals simultaneously. As the crystals became visible, various heating and cooling cycles were instituted to stimulate growth and purity over several days. In the near future, these crystals will be structurally analyzed for comparison of their magnetic and physical properties. Imidazole and related compounds constitute the backbone of histamine and many peptides involved in human biological processes. With the data of these types accumulated here, some previously unexplained biological chemistry and related phenomena may one day be explained.

Implementation of Gel Electrolytes in Rechargeable Lithium-ion Batteries. JENNIFER WADE (University of Iowa, Iowa City, IA 52240) KATHRYN STRIEBEL (Ernest Orlando Lawrence Berkley National Laboratory, Berkley, CA 94720) .
The use of a polymer gel electrolyte in a rechargeable lithium ion battery will help provide a mechanically stable and compact structure connecting positive and negative electrodes via a thin ion conducting layer of gel polymer. The properties of a successful gel electrolyte will create stable interfaces with the electrodes have an ionic conductivity of 1 mS/cm at ambient temperatures. Specifically, lithium ion conductivity, electrolyte uptake (swelling) and binding to electrode materials were investigated for commercial microporous polyolefin membranes (Celgard). With the aid of a poly (vinylidene fluoride) (PVdF) coating on the Celgard samples, bonding between the separator and the electrodes was possible. Moreover, the microporous character of the membrane allowed for a much greater swelling of electrolyte than predicted (=100% by mass). The conductivity obtained varied based on the composition of the membrane and whether the membrane was coated with the PVdF polymer host.

Applications of Synchrotron Based Technologies to the Forensic Examination of Ink and Paper. TOMMY WILKINSON (Fresno City College, Fresno, CA 93705) D. L. PERRY (Ernest Orlando Lawrence Berkley National Laboratory, Berkley, CA 94720) .
Synchrotron-based technologies, including Fourier Transform Infrared Spectromicroscopy (FTIR-SM) and XRay Fluorescence Microprobe (XFM), can be used for direct and rapid evaluation, characterization and identification of writing inks. These techniques can be used for the direct nondestructive analysis of inks on paper and other materials, without any mechanical or chemical destruction of the paper, and without having to extract or separate the inks. These techniques allow for very small sample size (less than 10 microns) and with very low quantities (less than 10 femtograms). These methods may also be useful in other areas of ink analysis, including, but not limited to, qualitative and quanitative analysis of the primary ink components, verification of the identical nature of several inks, and potentially determination of the age of the ink relative to the paper.