Phonon calc + structure visualisaiton

[joehart2001]

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Summary

Added phonon calc + DFT and MLIP relaxed structure visualisation

Also, about a 1.5x speedup in the calculation time which is nice

Linked issue

Resolves #

Testing

running all models now, matches results for mp-0a so far

[ElliottKasoar]

Generally looks great! I need to test it more carefully, but I've left some minor comments for now

[ElliottKasoar]

What's the main source of speedup out of interest?

[joehart2001]

What's the main source of speedup out of interest?

mutliple small factors:

• changed 3/6 of the ref outputs (qpoints, labels and connectiosn files) to one pkl file
• probably mlipx node overhead
• threadpool_limits
• yaml loading: CSafeLoader is the C-extension binding to libyaml which can apparently be 10-50x faster

[ElliottKasoar]

Works great from testing!

One small thing is that the scatter plot resizes when you open the second plot, which is a bit odd, but it's a lot better than it was.

[ElliottKasoar]

Looks good, thanks!