Can anyone identify the molecule (functional group?) shown horizontally on this new US postage stamp?

I believe the vertical one is Polyethylene terephthalate (PET). (The stamp is "Science" from the "STEM" issue of April 6, 2018.)

I don't know exactly what it is by looking at it, but my immediate thought is that it does give the appearance of something that might be used as a liquid crystal. I would have to check SciFinder to know for sure. The other molecule on there is 1,3,5,7-tetramethyladamantane, if you were interested. 

Thanks so much for your hypervigilance, hypervalent I! Of course, as happens so often, a good answer leads to more questions.

When you say "the other molecule is 1,3,5,7-tetramethyladamantane ," are you referring to the ball-and-stick model? (if so, wow! - what is it used for?)

Can you confirm my notion that the vertical one (structural formula) represents PET? And if the horizontal formula can't be exactly specified with a common name, is it possible to characterize it more generally (e.g. "a polymer with single and linked benzene rings"?)

Thanks again for your insight!

Yes, the ball and stick model. I am not sure that molecule specifically is used for anything in particular, but adamantane and its derivatives have many uses, from drug compounds (amantadine, eg), to catalyst systems, to making dendrimers. My group has published reviews on the first two.

The vertical molecule looks like PET, yes.  

I couldn't call the horizontal molecule a polymer. It also can't be given an exact name as part of the molecule is undefined (the -OR group). It is some sort of biphenyl compound, containing several ether linkages. 

Perhaps the best way to characterize it for a non-scientist would be "a complex organic compound with benzene rings"?

I don't know about that being the best way. It really depends on context / what information you want to relay. Detailed structural characteristics are probably not useful to most non-scientists, who likely wouldn't know how to interpret the jargon. 

I agree, it can be quite difficult to convey useful scientific information to lay readers without lapsing into jargon. (I think that's the reason many people get frustrated with science writing!) In this case I am writing about the postage stamp, and trying to explain (in a few words) the significance of the chemical formulas the designer chose for the illustration.  PET is easy; the other two are harder to summarize. Maybe "Organic molecules with complex ring structures"?

 

To be honest, I wouldn't call them complex. Adamantane, and the tetramethyl derivative in the stamp, is a product found in crude oil, if that helps. It is a caged hydrocarbon of the diamondoid family. I will look up the other compound tomorrow. I'm sure it has some significance beyond it simply having aromatic rings and ether groups. 

You could also attempt to contact the artists themselves. I'm sure they would know. 

Looks pretty complex to me   I really appreciate your willingness to share your considerable knowledge on this, hypervalent. I'll watch for any further comments you may have.