- Author
- Megan Cowie and many co-authors, CBN Nano Technologies, Inc., Ottawa
- Published
- 26 May 2026
- Kind
- Experimental physics preprint (arXiv version 1) with simulations
- Original
- arxiv.org/abs/2605.27250
- Subject
- Science and medicine
What it is
A team at CBN Nano Technologies reports positional and chemical control in mechanosynthesis. Molecules on a surface act as imaging probes and as reagents. The aim is to show repeatable atom-scale building of carbon structures.
What it says
- The authors say STM at 4 K moved C2 units onto prepared silicon sites.
- A molecular tool both images the surface and carries the C2 unit, the paper says.
- Repeated donation built patterns, including nine C2 units (18 carbon atoms) in an X shape.
- Adding a second C2 gave a four-carbon chain, IR-C4, which the authors call previously unreported.
- They report yields of 93% for IR-C2 and 84% for two side-by-side IR-C4 units.
- One of the most common off-target outcomes was hydrogen abstraction, in nine of 351 interactions.
- Simulations suggest the transfer runs downhill once mechanical motion clears all barriers.
What evidence it gives
The paper shows microscope images, simulated images and simulated reaction paths. It gives outcome counts, such as 184 of 197, with confidence intervals. Assignments of structures rest on indirect matching, not direct atom views.
Interests and limits
The authors work for CBN Nano Technologies, which also funded the work. The page shows version 1, with no peer-review status. Only C2 units on one surface were tested, at 4 K. The Supplementary Materials, cited for extra evidence, were not available on the page.