Traditional atomic van der Waals materials such as graphene, hexagonal boron-nitride, and transition metal dichalcogenides have received widespread attention due to the wealth of unusual physical and chemical behaviors that arise when charges, spins, and vibrations are confined to a plane. Though not as widespread as their atomic counterparts, molecule-based two-dimensional (2D) layered solids offer significant benefits; their structural flexibility will enable the development of materials with tunable properties. Here we describe a layered van der Waals solid self-assembled from a structure-directing building block and C60 fullerene. The resulting crystalline solid contains a corrugated monolayer of neutral fullerenes and can be mechanically exfoliated. The absorption spectrum of the bulk solid shows an optical gap of 390 ± 40 meV that is consistent with thermal activation energy obtained from electrical transport measurement. We find that the dimensional confinement of fullerenes significantly modulates the optical and electronic properties compared to the bulk solid.

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When characterizing students’ item-solving strategies, methods such as interviews and think-aloud protocols are often used. However, these measures provide limited information about sub- or preconscious signals and cognitive processes that also affect students’ item-solving strategies and abilities. A growing number of researchers in chemical education research have begun to address this gap by using physiological measurements to assess cognitive load (e.g., heart rate and EEG) and to look at item-solving strategies (e.g., via eye tracking). One physiological measure of cognitive load that has been well-documented in psychology literature is pupil dilation. In this study, two streams of eye-tracking data (gaze and pupillometric data) were combined to reveal information about what mental tasks general chemistry students were engaged in as they answered Chemical Concepts Inventory (CCI) questions (gaze stream) and how those mental tasks elicited changing levels of cognitive load (pupillometric stream). We found that, for complex multiple-choice tasks, pupil dilation fluctuated throughout the course of solving the item. For a more straightforward true/false task, there was a marked difference in pupil signal between participants who correctly answered the question and those who incorrectly answered it. Those who correctly answered the question had linearly increasing pupillary signals, whereas those who incorrectly answered had pupil signals that more closely resembled those observed during the multiple-choice tasks. Interpretations of these differences are supported using retrospective interviews and previously published literature about CCI items.

The gap between graduate research and introductory undergraduate teaching laboratories is often wide, but the development of teaching activities rooted within the research environment offers an opportunity for undergraduate students to have first-hand experience with research currently being conducted and for graduate students to develop communication and pedagogical skills. We describe the development, evaluation, and redesign of a Microsoft Excel-based activity where data analysis from contemporary research was adapted into a data analysis training exercise, requiring undergraduate students to engage with the data by performing a series of analytical tasks guided by commentary from the researcher. In addition to learning common data analysis techniques, this exercise provided an opportunity for undergraduate students to practice problem solving and collaboratively work through trouble-shooting. Throughout the activity development, multiple iterations allowed the authors to explore the impact of different pedagogical approaches including, but not limited to, student-prepared questions for the graduate student author that were used as a starting point for an in-class discussion of the research findings, techniques, considerations, and future goals. This conversation between general chemistry students and the graduate student researcher was coupled with an in-person laboratory tour or video introduction by the researcher. These activities humanized the research enterprise for the undergraduate students and serve as a model for future collaborations between research and instructional laboratories.

Productive problem solving, concept construction, and sense making occur through the core process of abstraction. Although the capacity for domain-general abstraction is developed at a young age, the role of...