Mechanosynthesis adapter molecule

Context: Early mechanosynthesis with macroscale SPM systems

A stiff-core molecule typically with three or more "legs"
that functions as adapter between the SPM-needle-tip-apex
and the actual mechanochemsitry of the mechanosynthesis process.

Advantages

Advantages compared to "sharp" (i.e. typically >20nm radius) SPM tips.
What images (and manipulates) there is typically the edge of a more of less slanted apex terrace.
Assuming no oxidation that could cause more covalent and more complex apex structures. (e.g. CuOx tips).
Mechanochemistry happens at the mechanochemically active site, the mechanophore.

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Fewer possible SPM-needle-tip-apex configurations.
Rather than all sorts of needle-tip-apex-monolayer-island-corners
at all sorts of angles just a single atom as active apex.

Overall more reproducability due to the smaller possibility space.

Better options and control of the chemistry at the mechanochemically active site (mechanophore).
Central atom element and first and second surroundings elements, all choosable and adjustable to some degree.
Cooseable outside of the typical options for needle materials (PtIr, W, pure Si, …).
Particularly low period semi-metals and non-mentals with stroingly directed covalent bonding chemistry become accessible.
Particulatly ones that are better suited for near equilibrium energy mechanosynthesis with path dependent outcome.

Better control of the orbital orientation
The orbital orientations/directions can be controlled in a way that is not constrained by the SPM needle apex material and structure.
With a strongly covalently behaving element rather than more metallic less directed bonding
this becomes even more relevant (e.g. sp3 orbital facing up).

More mechanically stable.
Especially compared to coinage metal SPM-needle-tip-apices with low energy sliding barriers.
Stronger interaction forces are less likely to change the tip-structure.

Providing some spacing between the mechanophore and the interaction site.

All that rather than a fragile and chaotic tip that needs excessive re-characterization all the time
breaks down regularly and provides little control over and separation of concerns of
abstraction, deposition, and tip repair.

Disadvantages

Less electrically conductive:
This can make imaging harder. High voldates low currents.
Especially bad for dI/dV spectroscopy.

There may be some molecule types that are a bit more conductive which
also may come as a a trade-of to mechanical stability.

Relation to mechanosynthesis mode

See page: Mechanosynthesis modes

Context: Mechanosynthesis in advanced productive nanosystems like nanofactories

In future advanced systems adapter molecules may typically seamlessly integrate into crystolecules.
Making for mechanosynthesis adapter crystolecules:
– feedstock carrier crystolecules
– mechanosynthesis tool crystolecules

Related

• Mechanosynthesis_(disambiguation)
• Mechanosynthesis
• Force applying mechanosynthesis
• Mechanosynthesis modes

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• Scanning probe microscopy & Stiff cantilever AFM

External links

(wiki-TODO: Add links to papers of self assembling monolayers (SAMs) on gold surfaces. Convert to proper references.)

On gold:

• 2023 – Controlled Vertical Transfer of Individual Au Atoms Using a Surface Supported Carbon Radical for Atomically Precise Manufacturing
• 2013 – Tailoring electronic states of a single molecule using adamantane-based molecular tripods
• 2011 – Multidentate Adsorbates for Self-Assembled Monolayer Films
• 2010 – Rigid adamantane tripod linkage for well-defined conductance of a single-molecule junction
• 2008 – Self-Assembly and Scanning Tunneling Microscopy Tip-Induced Motion of Ferrocene Adamantane Trithiolate Adsorbed on Au(111)
• 2007 – Hierarchical Chiral Framework Based on a Rigid Adamantane Tripod on Au(111)
• 2006 – Rigid Molecular Tripod with an Adamantane Framework and Thiol Legs. Synthesis and Observation of an Ordered Monolayer on Au(111)
• 2002 – Nanoscale Tripodal 1,3,5,7-Tetrasubstituted Adamantanes for AFM Applications