PennyLane is an open-source quantum software platform for quantum

Interesting to see it mention quantum chemistry, could anyone familiar with the field chimu in on whether it is viable to get accurate bond energies? It mentions Hartree-Fock, but I thought that that wasn't accurate enough to find transition states.

Re: PennyLane is an open-source quantum software platform for quantum

#8

Post by dbwy-quantum » Fri, Jul 17, 2026, 9:01 PM UTC

smj-edison wrote: post #7

Interesting to see it mention quantum chemistry, could anyone familiar with the field chimu in on whether it is viable to get accurate bond energies? It mentions Hartree-Fock, but I thought that that wasn't accurate enough to find transition states.

Indeed, Hartree-Fock (HF) is often not the suitable choice for treating bond breaking processes (what you want to model to compute a bond energy), as the "interesting" part of that process transverses what we call "multi configurational states" (i.e. states in which the electrons are strongly entangled, exactly what HF can't describe well). For these kinds of problems, you need to resort to methods that can describe these processes (like full configuration interaction, etc) which are pretty hard to perform classically.

As it turns out, quantum computers are really well positioned to solve these kinds of problems through algorithms such as quantum phase estimation (QPE). If you want to see a worked out example of how one would do this (including the entire classical part of the workflow, where only the "important" part is put on the quantum computer), check out the QDK for Chemistry library and our example notebooks here

https://github.com/microsoft/qdk-chemistry/blob/main/example...