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qcscine / sparrow

https://scine.ethz.ch
BSD 3-Clause "New" or "Revised" License
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Saving a Molden file? #2

Closed ghutchis closed 4 years ago

ghutchis commented 4 years ago

I'm curious to try sparrow with Avogadro 2 - one thing I'd really like is to visualize the MOs using a Molden or WFN file, cube, etc.

Any way to save the wavefunction, electron density, etc.?

francesco-bosia commented 4 years ago

Hi, thank you for your feedback!

It is no problem to have a Molden file output in the next release. Is a Molden file containing STO exponents ok, or does Avogadro require the corresponding GTO expansion? Most NDDO methods use a STO basis set. They do not explicitly compute the integrals over the basis functions though, as they invoke some approximation for them, except for the overlap matrix. For it, we use a STO-6G basis.

Both STO or GTO (STO-6G) are viable options for us, we just need to know which one works best for Avogadro.

By the way, we will have Python bindings in the next release. If you would like to interface Sparrow using Python directly, please let us know and we can discuss if there are particular things to be bound.

ghutchis commented 4 years ago

Avogadro has support for STO, but I'd guess for visualization, most people will find STO-6G to be easier. I don't know if every code that reads Molden files expects STO sections.

ghutchis commented 4 years ago

As far as the Python bindings, I think the first step would simply be energies and gradients given a coordinate file - Avo2 has an open interface for the interactive optimization / MD.

weymutht commented 4 years ago

We just released version 2.0.0 of Sparrow. It allows you to save a Molden file (with the option -W). In addition, it now has Python bindings which allow to calculate the energy and the nuclear gradient. You'll find an example code snippet in the manual.

I'm closing this issue. Feel free to reopen it if you deem it necessary.