View source for Intercrystolecular levitation

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== Omnidirectionally attractive bearings ==

[[File:0415tenseBear.gif|400px|thumb|right|Bearings can be stable despite attractive interactions between their surfaces – Graphic by Eric K. Drexler]]
[[File:Crystolecule-vdW-questions levitation-omniattractive.png|400px|thumb|right|Omnidirectionally (or baleancedly directionally) attractive geometry configurations.]]

Unlike with macroscopic magnets 
When [[crystolecule]]s (or nanoscale surfaces in general) approach each other <br>
there is a maximal attractive force distance to full surface to surface contact <br>
(that shall be defined as the energy minimum here) <br>
after which the attractive force shrinks again. <br>

This is unlike magnets attracted for ferromagnets or other magnets at the macroscale <br>
where attractive forces only go mootonically up until a very sharp full macroscopic contact. <br>

At the nanoscale due to the weakening of the attractive forces on close distances <br> 
it is possible to make bearings that levitate a part in such a way <br>
that all forces are are attractive but mutually compensating. Or zero. <br>
  
Related: Nonmonotonicity of [[nonbonded forces]]. <br>
See main page: '''[[Negative pressure bearings]]''' <br>

== Stable electrostatic levitation ==

{{todo|This needs more analysis and discussion. Especially about in how far Earnshaws theorem applies here.}} <br>
{{wikitodo|this may deserve it's on infographic too eventually.}}

This is in analogy to ultra cold atom ion crystals short before Bose Einstein condensation. An ion Coulomb crystal. <br>
Just that charged crystolecules are levitated instead. <br>
Side-note: Laser-cooling of charged [[crystolecules]] (just like with atoms) should be possible. <br>
This is more far range levitation though. <br>

A big difference is that unlike free floating single atoms crystolecules have non-degenerate 3D shape <br>
(3 main aces of reference coordinate system specifyable) and thus <br>
their rotational orientation can be fully constrained beside merely their position. <br>
That is: Given the electrodes are close enough to make sufficiently anisotropic local electric fields. <br>

== Surface dipole based repulsion ==

[[File:Crystolecule-vdW-questions levitation-Keesomrepulsion.png|400px|thumb|right|Using surface embedded orientation enforced dipoles for stronger repulsive force. A rare (and it seems the only possible) case of repulsively acting vdW force. The Keesom force part of the vdW force, interaction between real dipoles.]]

This is an odd edge case of the van der Waals force <br>
and the only one that can act acts repulsively. <br>

Specifically the Keesom force subset of the der Waals forces. <br>
Interacting between two real (non-virtual) dipole pairs. <br>

In biological nanosystems (molecular biology / proteins) <br>
dipoles are rarely forced into a mutually repulsive orientation <br>
and while that may still happen sometimes in enzymes and such <br>
even more dipoles are collectively forced in a repulsive orientation such that forces sum up. <br>

In the case of crystolecules it might be possible though to intentionally force such situations. <br>
Surface passivization on [[crystolecule]]s with elecronegative elements like nitrogen or oxygen <br>
will create dipoles that are forcibly fixed in their orientation in space. <br>

Repulsive alignment may be enforced by e.g.an piston in cylinder arrangement. <br>
Or any other sort of arrangement really. <br>
One mice example being pencil on magnet flotation toys. <br>
This one also illustrates a fundamental limitation. <br>
There is no static levitation possible. <br>
At least one point needs to be supported. <br>
Reason being Earnswahs theorem. <br>
Net neutral things can't be statically levitated. <br>

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{{todo|Some questions deserve more concrete answers.}} <br>
❓Q: '''Can electronegative passivations (N,O) facing same or other elecronegative passivations yield repulsive surface-surface interactions?''' <br>
'''If yes, then how repulsive qunatitatively?''' <br>

== Related ==

* [[Intercrystolecular interactions]]
* [[Intercrystolecular snapping modes]] 
* [[Intercrystolecular levitation]] < you are here
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* '''[[Levitation]]'''
* [[Atomically precise bearings]]
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* [[Intercrystolecular forces]], [[Nonbonded forces]], [[Nonbonded interactions]], [[Van der Waals force]]

== External links ==

Wikipedia:
* [https://en.wikipedia.org/wiki/Coulomb_crystal Coulomb crystal]