Surface interface
The term surface interfaces (or short sinterfaces) may be used for the unpassivated surfaces of diamondoid molecular structural elements (DMSEs of technology level III). Unpassivated means that open unsaturated bonds (chemical radicals) are present. Those act (in practical terms) simply as androgynous connection points. To have anything to assemble for each surface interface of an DMSE there muts be at least one type of DMSE that provides at least one complementary surface interface. Since the formed bonds are indistinguishable from the bonds within the solid merging/welding together of two complementary sintefaces is an irreversible process and leaves a seamless joint. When trying to break the sinterface apart again some random fracture will occur.
For larger areas correct internal atomically precise bond forming may be an issue [Todo: include reference] For the best results one can begin to form the bonds from one side then rotating the two parts around the location of the first formed bond(s) closing the remaining wedge of open space in a slowing down scissoring motion while zipping the radicals together at a constant rate.
For some crystallographic surfaces of diamond surface reconstruction is an issue. This has been analyzed [Todo: add link to nanodiamond study]. The surface reconstuctions that are frequently observed today are often caused by heating the sample way above ambient temperature. When building DMSEs Mechanosynthesis can be done slow enough that such extreme heating does not occur. This may allow for the creation of more unstable crystallographic surfaces. Wether to use them is another question.
Sidenote: If a sinterface lies on a single plane all the bond directions are normal to the plane and the sinterface has at least twofold rotational symmetry then the complementary surface is identical to the original.
Sparse sinterfaces designed to have only few covalent connection points per area and conical widening behind them can be taken apart reversibly. microcomponents containing such structures need to be moved back into vacuum (possibly down to assembly level II) if those joints are ought to be disassembled.
When a bunch of DMSEs are merged together enclosing some DMMEs undisassemblable monolithic diamondoid machines are created. The maximal size in a nanofactory with minimal inert zone is a whole microcomponent.
Note:
- the zipping speed for radicals is limited by "Radical coupling and inter system crossing".
- to merge bigger parts accurately conical alignment pegs can be used (Nanosystems Figure 14.1.)
External references
- Nanosystems 9.7.3. Covalent interface bonding
