American Pi + Old Ideas Revisited = A Few Thousand New Words For The Gallery

[Slipping into terminal blog mode for a moment] This past week saw (1) the second Technology Roadmap for Productive Nanosystems meeting at Brookhaven National Labs and the press release for (2) Nanorex’s first major educational outreach project as part of (3) the COSMOS (California State Summer School for Mathematics and Science) summer program. The purpose of (1) is to develop science and technology pathways with the intent of realizing the full potential of molecular nanotechnology, the purpose of (2) is to enable researchers, like myself, to have the best possible tools for designing molecules and nanosystems in order to go into experimental work with the most complete understanding of their properties, and the purpose of (3) is to make sure that we (that’s the world) will have researchers in the future capable of making it all happen (and, in case you’ve not been following the news, we need all the help we can get in the sciences).

The next major update to NanoEngineer-1 includes all of the force field parameters required to simulate carbon nanotubes and other structures with extended pi-systems. In anticipation, I began sorting through some very old designs of mine that I promised to revisit once computers and software became useful enough to allow for their simulation. Fortunately, the state of technology has moved faster than Barnard’s Star, so the old designs are rapidly being overwritten with new ideas. As for the gallery timing, I just completed some rerendering of gallery images for an upcoming article I’ll link to when it’s available, part of my work on the roadmap involves addressing steps to go from current technologies to motifs described in the new images, and, of course, Christine Peterson was kind enough to link to me in a recent nanodot post and I abhor the idea of having all the same old images up in the event anyone ever links to me again.

Some Brief Descriptions

The first image is of a non-covalent nanotube junction assembly that I first presented back in 2002 at the Foresight Institute 10th Conference on Molecular Nanotech. The design uses tapered nanotubes of identical radius and chirality (two things we can’t do yet in the lab, although you can buy the bulk products), molecular hinges composed of molecular fragments containing dative/dipolar bond donors and acceptors (which I presented with references and price lists for the components), and the MM2 force field with added terms used to model the dative interactions (which is older than I am and trusted to get the overall structures correct in this context). The goal was to design an octahedral junction that would, under ideal conditions, self-assemble. This structure just about maxed out the machine I had available at the time, but is now a 20 minute job to clean-up.

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The second design is a network incorporating both the dative junction assembly above and my ever-so-popular fused diamondoid carbon nanotube van der Waals crimp junction. The purpose of this design was to demonstrate a number of structural motifs in as small/model-able a system as possible for part of my Brookhaven TRPN talk. In order to show the detail in this structure, you can click on this image to see a larger version. While I don’t wish to engage in a conformational entropy debate at the moment, I was pleased to include in the presentation of this structure a recent JACS paper out of Prof. Alex Zettl’s lab concerning nanotube solvation and nanotube/protein coupling.

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Taking a step back to the present, the last image is the crystal cell of corannulene, the subject of a submitted article on solid-state DFT and crystal geometry prediction/interpretation. Not really nanotech, but these are pi-systems (sticking with a theme) and the image came out nicely after some tweaking. I will save the thorough explanation for if/when the article gets accepted.

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www.foresight.org/roadmaps
www.bnl.gov
www.nanorex.com
epc.ucsc.edu/cosmos
en.wikipedia.org/wiki/Carbon_nanotube
en.wikipedia.org/wiki/Barnard%27s_star
www.foresight.org
en.wikipedia.org/wiki/Dative_bond
en.wikipedia.org/wiki/Force_field_(chemistry)
pubs.acs.org/cgi-bin/abstract.cgi/…/abs/ja060276s.html
www.physics.berkeley.edu/research/zettl

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