Comment by MrEldritch
7 hours ago
The concept is interesting, but I'm getting a lot of red flags from this - there's no experimental data or proof-of-concept work at all, which makes this feel more like a blue-sky "Look what we could do if we could arrange atoms however we wanted!" pipe dream in the Drexlerian mode. Something about the writing style's also pinging my LLM radar, which while not disqualifying in-and-of-itself is very discouraging in combination with the other funkiness. The chemistry and manufacturability strike me as questionable in particular, and I'm not convinced the physics of reading and writing are nearly as clean as the author seems to think.
(I'm also unclear how the bit is supposed to actually flip under the applied electric charge without the fluorine and carbon having to pass through each other.)
The fluorine doesn't pass through carbon. It passes between two neighboring carbons through a C-C gap of 2.64 Å at the transition state. This is pyramidal inversion — the same mechanism as ammonia (NH₃), but with a 4.6 eV barrier instead of 0.25 eV. The transition state geometry is computed and verified with one imaginary frequency.
> with one imaginary frequency
Technical note, because it's jargon:
"Real" means position = A * sin(w * t)
"Imaginary" means position = A * expt(w * t)
(because expt(w * i * t) = cos(w * t) + i * sin(w * t))
If you calculate in a computer an ammonia molecule with all the atom is a plane z = 0 (instead of the usual piramidal shape), then the N in the center is in an inestable equilibrium and the N does not make small vibrations like z = expt(w * t).
It makes a big "imaginary" vibration like z = expt(w * t) that is exponential for a short time while z is almost 0, and then the approximations don't apply and it reach the z of the usual shape at equilibrium.