The development of expertise in chemical information literacy requires practicing these skills in the context of chemistry work. The integration of information literacy in problem-based learning is an instructional strategy that can be used to situate skill development in the chemistry classroom. This work describes a mixed-methods approach to investigate the information seeking behavior of upper-level students working collaboratively on a semester-long inorganic chemistry problem. Audio recordings were collected during problem solving sessions and analyzed to investigate the strategies students used to find outside information required to identify an unknown compound. These students had prior coursework in chemical information literacy, and an information literacy test was used to establish the baseline of their knowledge and skills, and its development through the course. Student written work was analyzed to determine the outcomes of students’ information searching processes. Finally, semistructured interviews were conducted to contextualize the results. Discourse analysis of student planning sessions demonstrated that students exercised skills taught in prior coursework but tended to rely on Google, where they did a broad search before turning to scientific databases and more scholarly sources. The information literacy test and interviews revealed that students recognized the need to use “better” sources but perceived Google to provide a more expedient search. Students also struggled to apply their information literacy skills when the chemistry content was new and unfamiliar, indicating that information-based instruction should be integrated into chemistry courses.

Polymerization of the [(η5-C5H4(CH2)8CHCH2)Mo(CO)3]2 complex by acyclic diene metathesis polymerization (ADMET) is reported. The polymerization reactions were performed using Schrock’s catalyst, which resulted in formation of a polydisperse oligomer (M n = 2300 and M w/M n = 4.3) with Mo−Mo bonds in the oligomer chain. Under dilute solvent conditions, the reaction was shown to favor the formation of the ring-closing metathesis (RCM) product. The ADMET oligomer was photochemically degradable, and irradiation with λ > 520 nm light in CCl4 resulted in cleavage of the oligomer backbone and formation of the metal chloride complex [μ-C5H4(CH2)8CHCH(CH2)8C5H4{Mo(CO)3Cl}2]. The RCM product was also irradiated and the photochemical product is identical to that formed by irradiation of the oligomer. Copolymerization of [(η5-C5H4(CH2)8CHCH2)Mo(CO)3]2 with 1,9-decadiene using Grubbs’ second-generation catalyst resulted in a higher molecular weight oligomer (M n = 3400, M w/M n = 3.9).

Semiconductor nanoparticles, including cadmium selenide (CdSe) particles, are attractive as light harvesting materials for solar cells. In the undergraduate laboratory, the size-tunable optical and electronic properties can be easily investigated; however, these nanoparticles (NPs) offer another platform for application-based tunabilitythe NP surface. In the interest of exploiting these particles for solar applications, the surface can be tuned to facilitate charge transfer out of the nanoparticles to maximize photocurrent for high-efficiency, low-cost solar cells. This multiweek undergraduate laboratory experiment introduces students to semiconducting nanomaterials and to taking steps to ensure functionality of these materials for solar applications. The experiment includes the synthesis of oleic acid-capped (OLA) CdSe particles and a biphasic ligand exchange reaction to afford ionically functionalized CdSe nanoparticles capped with sodium 3-mercaptopropane-1-sulfonate (MPS). Both the CdSe-OLA and CdSe-MPS materials in this experiment are characterized for ligand binding and relative particle size distribution by FTIR, 1 H NMR, and UV−visible spectroscopies.

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Multiple exciton generation (MEG) and exciton recombination were studied by femtosecond transient absorption spectroscopy in PbS nanoparticles (NPs) capped with oleic acid (PbS–OLA) and 2,3-dimercaptopropane sulfonate (PbS–DMPS) ligands. Analysis of the transient absorption data showed that the PbS–DMPS nanoparticles exhibit increased rates of multi- and single-exciton recombination compared with the PbS–OLA nanoparticles; however, the MEG yield for both sets of particles was the same within experimental error. The origin of the differences in the exciton recombination decay rates is unknown, but it is speculated that it may be due to the ionic functionality of DMPS or to the different ligating atoms of the OLA and DMPS ligands. The PbS–DMPS nanoparticles were highly sensitive to the presence of oxygen, which caused a dramatic increase in nonradiative decay pathways, which can be mistaken for multiexciton absorbance and decay. Removal of oxygen eliminated the nonradiative decay pathways. Overall, this study showed that the dynamics of MEG can be modified by changing the NP ligand shell, a result that may be useful in the development of NP-based thin-film solar devices.