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An innovative first- and second-year laboratory course sequence is described. The goal of the instructional model is to introduce chemistry and biochemistry majors to the process of research participation earlier in their academic training. To achieve that goal, the instructional model incorporates significant hands-on experiences with chemical instrumentation, beginning in the first semester and continuing through the fourth semester. The model also strives to instill within students an understanding of the social aspects of a working research laboratory, where members enter and gradually change roles based on increased experience and responsibility. An implicit assumption in the instructional model is that students gradually move from verification experiences to more open-inquiry experiences, which mimics the process of joining a working research laboratory. The capstone experience in this model is a laboratory stand-alone course, where students design and implement experiments related to faculty research projects within the department. Ideas for broader implementation of the model at various types of institutions are also suggested. A paper describing the implementation of the model is forthcoming. (Contains 2 tables.)

Investigates the changes in students' understanding of chemistry concepts when concept mapping is used as an instructional method and assessment technique. (Contains 24 references.) (YDS)

The N-protonated bimercaptoethanediazacyclooctane serves as a bidentate dithiolate ligand to oxidized Fe(NO)(sub 2) mimicking Cys-X-Cys binding of Fe(NO)(sub 2) to proteins or thio-biomolecule. These molecules are useful for in vivo studies of NO degradation of iron-sulfur clusters in ferredoxins.

The activation of alkenes and H2 by [Fe]-H2ase model complexes is presented. It is found that the metal hydride derived from the heterolytic H2 splitting is important intermediates along the reaction path of the hydrogenases.

Research has been conducted on the [Fe]-hydrogenase model complex. The protonation of this complex in producing species with high field (super)1 H NMR resonance has been carried out and the results indicate that this species has been isolated as a stable salt.

Research has been conducted on the N (sub)2 S (sub)2 Ni complexes. The X-ray crystal structures and chemical properties of the Ni and the S-templated macrocyclic NiBr (sub)2 complexes have been investigated in relation to their magnetic, spectroscopic and electrochemical properties.

The relative responses of the pyramidal organometallic fragment, FE(CN)2(CO), to electronic changes as related to its effect on oxidized forms of [NiFe]hydrogenases were investigated. In addition, the vibrational spectroscopy of the unit was analyzed with respect to band positions and intensity ratios as influenced by solvent and counterion. Results showed that the FE(CN)2(CO) fragment senses electron density changes about the pseudo-octahedral model complex in a consistent and predictable manner.

Research has been conducted on hydrogenase enzymes. The authors report that the hydrogen uptake in the enzymes can be investigated via H/D exchange reactivity, and that diiron(I) complexes serve as structural models for the iron hydrogenase active site.

It has been possible to identify reactivity of FeIFeI and [FeII-H-FeII]+ complexes that is in alignment with the chemical characteristics/activity of the enzymes. This work confirmed the earlier finding that CH3-CN is a better ligand for FeII than H2 is.

A study was conducted to examine product state distributions and kinetics associated with semiconductor photocatalytic surface reactions, emphasizing the photodegradation of CH2Cl2 over a TiO2 photocatalyst. The progress of photocatalytic oxidation of CH2Cl2 during the presence of O2 was determined using infrared spectra. Results indicated that the production of phosgene could be minimized by a factor of 3 using a long-pass filter. It could also be eliminated by minimizing the shorter wavelengths of light.