Submitted by Maggie Geselbracht / Reed College on Fri, 10/24/2008 - 21:11

I had an extended conversation with a colleague over the weekend about what he (as a non-solid state chemist) should convey to students about solids.  Happily, this conversation was made all the more pleasant by L'énorme (GIANT cone of Belgian fries) and some good beer.  Here's what I think are the 7 things that students should know about solids coming out of an inorganic chemistry course.  Maybe you don't have time or expertise do all 7, but some is better than none.

1. Visualizing structures of solids:  Unit cells, coordination numbers and stoichiometry in the structures of metals and nonmetals, basic ionic solids, and examples from complex structure types (i.e. perovskites or zeolites or MOFs)

2. The possibilities offered by the formation of solid solutions: i.e. tuning the band gap in GaAsxP1-x

3. Basic electronic structure of metals vs. semiconductors vs. insulators

4. Electrical conductivity in solids: electrical vs. ionic conductivity, possibly superconductivity

5. Doping in semiconductors: n-type vs. p-type silicon, for example

6. Magnetism in solids: diamagnetism, paramagnetism, ferromagnetism, antiferromagnetism, and ferrimagnetism (even a basic understanding here of what the difference is between these three types of magnetic ordering is fine)

7. Some discussion of the inorganic chemistry of a technologically important solid or class of solids: This could be drawn from semiconductors, LEDs, lithium ion battery materials, superconductors, catalysts, or magnets.  The important point is to connect the properties of the material in some way to structure and composition.

 What do you think of this list?  Other topics you would add?  If you only had time to do 3, which 3 are most important to you?

Michael Lufaso / University of North Florida
    It is a nice list and the topics you list are all important. Perhaps include the concepts and words 'defects and non-stoichiometry' as part of '#4. Electrical conductivity in solids'.  If the list is expanded to 8, another possible topic is Preparative and characterization methods: solid state synthesis, diffraction, Bragg's Law. These are often significantly different from typical inorganic coordination compound synthesis and characterization.

My 3 most important:  Visualizing structures of solids, types of magnetism in solids, Doping in semiconductors/bands

Sat, 10/25/2008 - 13:50 Permalink
Nancy Williams / Scripps College, Pitzer College, Claremont McKenna College

Well, as the beer-swilling, L'enorme-munching colleague in question, I think this is a great list. In actuality, I think I ended up doing 1 in a surface way, 4 more in a monolayer fashion, 3, 5, and 7 in bulk (or as well as I'm likely to be able to do as an outsider), and 6 not at all. What I like most about this list, is it gives me a method of....well, not to use a dirty word in public, but, Assessment. It gives me something I can come back to in a year, and say, "OK, this year, I really want to tackle magnetism in solids and so more complex structures...these other areas are fine until those get fixed."

To me, the limit isn't so much time (though there is that). The limit is that in this course, I'm always balancing between optimally covering the field and giving the best course I can give. I could teach a fantastic course in mechanistic organometallics, but that would short the students. I can give equal time to all areas, but then I would spend most of the course teaching badly, since I'd be teaching material for which I lack the comprehension depth to bring anything into the classroom besides a thorough reading of the textbook chapter. That would short the students.

As a result, at the end of the day, I teach a very specialized course which I'm trying to make a little more general every time I teach it as my own knowledge of the field grows. Eventually, I'll be smart enough that I'll feel like I have so much knowledge that I have to teach my students that I just can't do it all in one semester, but I'm a ways from that yet, and by then I'll probably start forgetting that material through senility. Come to think of it, that latter process may already have begun-I can't remember.

Sun, 10/26/2008 - 01:27 Permalink
Chris Mullins / University of Kentucky

So, I have a "problem"...I've volunteered myself to give a 50 minute lecture highlighting Magnetism to a small group of students that are a combination of 2nd semester general chemistry (will have spent 4 days on Trans metals) and Materials Chemistry class.

Any good suggestions on how to approach this would be greatly appreciated.



Fri, 11/07/2008 - 19:41 Permalink
Hilary Eppley / DePauw University

In reply to by Chris Mullins / University of Kentucky

Hi Chris, Are you more interested in introducing bulk properties or molecular properties of magnetism? Those would be two very different lectures! I would think the bulk properties (such as ferro-, ferri, and antiferromagnetism as well as some of the newer single molecule magnet stuff) might be more interesting overall, especially to the Materials Chemistry students. --Hilary
Sun, 11/09/2008 - 20:41 Permalink
Chris Mullins / University of Kentucky

In reply to by Hilary Eppley / DePauw University

Thanks Hilary,


This is kind of the way I was you know of any particularly good resources I could point out?



Sun, 11/09/2008 - 22:06 Permalink
Hilary Eppley / DePauw University

In reply to by Chris Mullins / University of Kentucky

Actually the first Chapter of my Ph.D. thesis gives a pretty good introduction (and about 100 refs).  I don't seem to have an electronic copy around since I wrote it so long ago, but I'd be happy to scan it and email it to you later today (assuming I don't go into labor in the meantime.....).  I am guessing that the Teaching General Chemistry, a Materials Science Companion has some good sections on magnetism (Maggie correct me if I am wrong).  I know there is a neat demo in there of paramagnetism vs ferromagnetism vs diamagnetism where you put MnO2, Mn2O3, KMnO4, and Fe in gelatin capsules and look at their relative responses to a really strong cow magnet.  You just have to be careful as the gelatin capsules get sticky if you handle them too much.  Ferrofluids are always fun too--there is a J Chem Ed article on making them, but you can buy them as well (can't remember where at the moment), but you can talk about ferrofluidic ink in currency and show the response of a dollar bill to a strong cow magnet (works best if you hold it off the edge of the bench and pull it downward with magnet).  Somebody actually used ferrofluids in an art exhibit that came to our campus a couple of years ago--that was really cool! There was a vat of ferrofluid with magnets moving underneath and it was supposed to represent some sort of alien life form.  I'll try to send you that thesis chapter if you think it would be helpful--let me know if you have any other  questions or want me to track down other sources!   --Hilary
Mon, 11/10/2008 - 06:01 Permalink
Barbara Reisner / James Madison University

I agree with Maggie on this one.  If I had to whittle my list down to three, it would be 1, 2, and 7. Structure (1) is critical for any understanding of the topic. Nonstoichiometry (2) is what makes solids so different from molecules. And properties (7) are how we are going to convince them how solids are cool and worth looking into deeper.

Of course, this past year, I've had a number of students send email and say the most useful thing they've learned from the units in solids is symmetry in plane and space groups. This certainly isn't the answer that I would have expected!

Wed, 03/11/2009 - 17:06 Permalink