Nanoscience

19 Mar 2020

Online Seminar Talks

Submitted by Amanda Reig, Ursinus College
Evaluation Methods: 

Student summaries are simply graded as complete/incomplete and are checked to see that they did in fact watch the video. If student summaries are felt to be lacking substance or incomplete, we will indicate areas they can improve on future summary reports.

Description: 

In an attempt to find a substitute for our chemistry seminar program, I have found a number of YouTube videos of chemists giving seminar lectures, mostly between 2017-2020. The topics span a range of chemistry disciplines, and are all around 1 hour in length (typical seminar length).  I have not watched them, so I cannot vouch for video quality. Feel free to add additional links in the comments below if you know of or find any great talks.

We will ask students to select and watch a certain number of lectures from the list and then write and submit a one-page summary of the talk.

Prerequisites: 
Course Level: 
Learning Goals: 

A student should be able to summarize the key points of a lecture presented by a seminar speaker.

Corequisites: 
Time Required: 
1 hour
14 Mar 2020

Solid State Structures tutorial

Submitted by Terrie Salupo-Bryant, Manchester University
Evaluation Methods: 

I grade the Solid State Structures tutorial answer sheet (44pts) in conjunction with the Problem Set to Accompany the Solid State Structures tutorial (26 pts) that incorporates concepts from the tutorial.

Evaluation Results: 

The average score (n=32) is 60pts out of 70 (86%).  Scores on the Problem Set tend to be about 5 percentage points higher than on the tutorial.  Students usually spend some time calculating the length of the unit cell edge, a, in terms of the radius (r) of an ion/atom for each of the basic unit cells.  Commonly they substitute diameter for radius or make errors in their trigonometry (see doi.org/10.1021/ed400367x  for derivation).  They also have difficulty seeing an empty hole which causes their percentage of filled octahedral and tetrahedral holes to be incorrect.  I added Figures 6 and 7 for fcc in order to help students in the future know where to look for the holes.  Visualizing 3D structures can be a challenge even to visual learners.  The average score indicates that manipulating structures on the computer makes them more tangible to students.  Wrestling with the questions is often a group effort and an opportunity for students to explain their thinking to others.

Description: 

This tutorial will introduce students to some of the three-dimensional crystal structures exhibited by ionic and metallic solids.  They will examine the simple cubic, body-centered cubic, face-centered cubic, and the hexagonal closest-packed systems.  To facilitate visualization of the structures at the atomic level, they will use the Crystal Explorer website at Purdue University.

Corequisites: 
Prerequisites: 
Learning Goals: 

After completing this tutorial, students will be able to:

  • Identify and describe basic crystal structures from their unit cells.
  • Describe the relationship between crystal packing and unit cell.
  • Determine whether atoms/ions in a crystal structure are closest packed.
  • Locate tetrahedral, octahedral, and cubic holes in a unit cell.
  • Apply geometric relationships to determine the length of a unit cell edge in terms of the radii of its atoms/ions.
  • Determine the coordination number of an atom/ion in a crystal structure.
Implementation Notes: 

The Crystal Explorer website is a free resource that contains all of the images needed to complete this tutorial.

When I teach my foundations-level inorganic chemistry class, I have students use Ludwig Mayer’s Solid State Structures JCE Software to complete this tutorial; however, the software is no longer commercially available.  It utilizes the PCMolecule application which I am still able to access on newer computers by adjusting the compatibility settings.  The images in the software use the same color schemes as the structures in the Solid State Model Kit.  See Teacher Notes for further information. I don’t have students use the model kits, though I do assemble one or two structures for them refer to if they need. 

Students can complete the tutorial in one lab session or in multiple lecture sessions.  I currently use one lecture session to get them started and have them complete it outside of class as a homework assignment.

Time Required: 
2.5 hours (longer if using the Solid State Model Kit)
8 Oct 2019
Evaluation Methods: 

assessment of students will be preformed by grading their answers to the questions in the activity.

Description: 

This is a 1 Figure lit discussion (1FLO) based on a Figure from a 2015 JACarticle on synthesizing conductive MOFs. This LO introduces students to Metal-Organic Frameworks and focuses on characterization techniques and spectroscopy. 

Prerequisites: 
Corequisites: 
Course Level: 
Learning Goals: 

As a result of completing this activity, students will be able to...

  • define what metal-organic Frameworks and Post-synthetic Modifications are
  • understand MOF terminology and notation
  • discover how mass transport and electron mobility effect conductivity
  • calculate energies of electronic transitions in electron volts
  • make connections betweeen diagrams and material sturctures
  • compare optical and microscopy techniques
  • discover the concept of photocurrect and how it could be used in different applications
Implementation Notes: 

Students should be able to complete the activity without any prior knowledge of MOFs, although some introduction to MOFs and UV-vis absorption spectroscopy would be nice.

8 Jun 2019

VIPEr Fellows 2019 Workshop Favorites

Submitted by Barbara Reisner, James Madison University

During our first fellows workshop, the first cohort of VIPEr fellows pulled together learning objects that they've used and liked or want to try the next time they teach their inorganic courses.

7 Apr 2019

Encapsulation of Small Molecule Guests by a Self-Assembling Superstructure

Submitted by Shirley Lin, United States Naval Academy
Evaluation Methods: 

I have not yet implemented this LO. As with other literature discussions, instructors could collect the completed worksheets (by an individual student or in groups of students) for evaluation.

Evaluation Results: 

I have not yet implemented this LO so there are currently no evaluation results to share.

Description: 

This literature discussion focuses upon two journal articles by the Rebek group on the synthesis and host-guest chemistry observed with the "tennis ball." 

Corequisites: 
Learning Goals: 

After completing this literature discussion, students will be able to:

  • provide examples of supramolecular systems in nature that use reversible, weak noncovalent interactions 
  • define terms in supramolecular chemistry such as host, guest, and self-complementary
  • identify the number and location of hydrogen bonds within the "tennis ball" assembly
  • draw common organic reaction mechanisms for the synthesis of the "tennis ball" subunits
  • describe the physical and spectroscopic/spectrometric techniques used to provide evidence for assembly of a host-guest system
  • explain the observed thermodynamic parameters that are important for encapsulation of small molecule guests by the "tennis ball"
Implementation Notes: 

This LO could be used at the end of a traditional 2-semester organic chemistry sequence as an introduction to organic supramolecular systems, as an organic chemistry example within a discussion about inorganic supramolecular chemistry, or in an upper-division elective course about supramolecular chemistry. The LO topic, the "tennis ball," has a published laboratory experiment in J. Chem. Educ. (found here). Time permitting, instructors could have students read the article and complete the literature discussion before executing the experiment in the lab.

As usual, instructors may wish to mix-and-match questions to suit their learning goals.

Time Required: 
depends upon implementation; minimum of 20-30 minutes for the literature discussion if students read an d answer questions outside of class
3 Mar 2019

Supramolecular Chemistry Videos

Submitted by Shirley Lin, United States Naval Academy
Evaluation Methods: 

I have yet to use this resource with students and therefore have no assessment of student learning to share at this time.

Evaluation Results: 

I have yet to use this resource with students.

Description: 

The Rebek Laboratory homepage contains information on and molecular visualizations of a variety of host-guest systems developed by the research group over several decades. The theme behind this set of examples is the use of hydrogen-bonding to achieve self-assembly. Under the "Research" tab, one can find four videos with narration: an introduction to molecular assembly and three videos of specific examples of self-assembled host systems (the cavitand, the cylinder and the volleyball). In addition, at the bottom of the tab, there are links to JSmol files for 5 host systems (tennis ball, jelly donut, cylindrical capsule, softball, and tetrameric capsule) that allow the assemblies to be visualized interactively.

 

This is a great resource for faculty looking for ways to incorporate the new ACS Committee on Professional Training guidelines to discuss macromolecular, supramolecular, mesoscale and nanoscale systems within the framework of their existing curricula.

Corequisites: 
Learning Goals: 

I have not yet used this resource with students but here are some possible relevant learning goals.

After viewing the Rebek Laboratory Homepage web source, students will be able to:

1) classify various self-assembled host-guest systems by the number of molecular components forming the assembly

2) identify the number and position of the hydrogen bonds that are responsible for the assembly of each host

3) identify the functional groups on the components of the host systems that are responsible for hydrogen bonding

4) state the experimentally determined percent volume of space generally occupied by guests that are encapsulated in these host systems

 

Subdiscipline: 
Implementation Notes: 

I have yet to use this website in my teaching but I hope that it may be a resource in expanding our curriculum in supramolecular chemistry.

Time Required: 
depends on use
15 Jun 2018
Evaluation Methods: 

I typically evaluate this activity through class participation although the answer key is posted after class to let the students evaluate their own understanding of concepts.  The students do know that they will be tested on the material within the activity and usually I have a density problem on the exam.

Evaluation Results: 

This activity is designed to give the students more freedom as they move from the first density calculation to the last set of calculations.  Within the last set of calculations, they encounter a hexagonal unit cell so that may require some additional intervention to get them to think about how to calculate the volume of a hexagonal unit cell.

Description: 

This activity is designed to relate solid-state structures to the density of materials and then provide a real world example where density is used to design a new method to explore nanotoxicity in human health.  Students can learn how to calculate the density of different materials (gold, cerium oxide, and zinc oxide) using basic principles of solid state chemistry and then compare it to the centrifugation method that was developed to evaluate nanoparticle dose rate and agglomeration in solution.

 

Learning Goals: 

A student should be able to calculate a unit cell volume from structural information, determine the mass of one unit cell, and combine these two parameters to calculate the density for both cubic and hexagonal structures.  In addition, students will have an opportunity to read a scientific article and summarize the major findings, place data in a table, and explain the similarities and differences between the densities calculated in the activity and the experimental values that are reported in the literature.

Corequisites: 
Course Level: 
Equipment needs: 

None

Prerequisites: 
Implementation Notes: 

I have used this activity in our first semester inorganic chemistry course when we cover solid-state materials.  One thing to note is that I do use 2-D projections to describe structures and we cover that in a previous activity.  You could remove 2-D projections from this activity if it is not something that you previously covered.  

 

Time Required: 
This activity usually takes about 40 to 45 minutes.

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