Molecular Möbius Strip (1 Viewer)

[buchanan]

Has your maths teacher taught you about <a href="http://mathworld.wolfram.com/MoebiusStrip.html">Möbius Strips</a> yet? They are fun to make with paper and cut them up.

But they are even more fun to make at the molecular level.

Here is a recipe for making molecular Möbius strips: http://4unitmaths.com/molecularmobius.pdf

Ask your chemistry teacher about them.

 

[Slidey]

Hey, NOW you're talking my language!

Seems trefoil knots are also possible. Ah, the beauty of nature.

I suggest reading the Feynman talk linked to at the start of that page. Excellent preliminary reading for the nanotechnology enthusiast, though a bit dated now (50 years?).

 

[Trefoil]

Oh goody! I just loooove topology. It makes me orgasm.

 

[buchanan]

Analogous to cutting a paper Möbius strip is to break the double bonds with ozone.

This picture is from a 1982 article in C&EN: http://4unitmaths.com/cen1982.pdf

Note however that this must be done under carefully controlled conditions. First it has to be dissolved in dichloromethane and the dye Solvent Red 23 (Aldrich) added and then ozone treatment at -78^oC until the red colour dissapears so as to not add too much ozone and to not have the ozonolysis happen too quickly. Then quench it with an excess of dimethylsulfide, remove solvent at reduced pressure and purify by flash chromatography on silica gel.

I did not include this in my pdf because technically it's not part of the synthesis.

The first person to do this was Walba in 1982: http://walba.colorado.edu/index.html

Here is his 1982 article in the journal of the American Chemical Society: http://4unitmaths.com/walba1982.pdf

His papers are at http://walba.colorado.edu/Reprints some of which also describe how to make molecular trefoil knots.

 

[buchanan]

Here are some more recent articles:

<a href="http://4unitmaths.com/ajami.pdf">Ajami's 2003 article</a>

<a href="http://4unitmaths.com/ajami-supp.pdf">Supplementary material for Ajami</a>

<a href="http://4unitmaths.com/herges.pdf">Herges' 2006 article</a>

And for something much older (see Herges' paper for details):

<a href="http://4unitmaths.com/mobiussong.mp3">Bach's 1747 Möbius music (canon cancrizans)</a><p>

 

[buchanan]

More recently a bigger molecule was made in 2014.

Bigger ones have a problem whereby they are less stable and unravel. But it was made more stable with a palladium atom inserted into it which prevents it from unravelling:

Here is the article for more details: http://4unitmaths.com/Yoneda.pdf

 

[Paradoxica]

I completely understand why these things are cool.

But there is no emotional response elicited from within.

But this is cool. ish. I guess....

 

[omegadot]

And <a href="https://www.researchgate.net/publication/243715872_Flexible_Faraday_Cage_with_a_Twist_Surface_Charge_on_a_Mobius_Strip">here</a> is a very simple physical demonstration of the one-sided property of the Möbius strip that makes use of surface charge and can easily be done in a high school physics lab using nothing more than a Van der Graaf generator and some thin wire gauze.