QMCPACK / QMCPACK/qmcpack

Cusp Correction & nstates Issues in QMCPACK

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bug
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Description

I am trying to export CASSCF wavefunctions generated using QP2.
Because the converter treats all MOs as the number of states, after the conversion is done, I manually modify the HDF5 file so that the `MultiDet/nstate` group corresponds to the number of MOs in my CAS space (which is 30 in this case).

As a result, my converted file changes from:
```













```
to:
```












```
Please note that the key change is in the `nstates` and `size` attribute.
For reference, I have also included the QMCPACK output produced by the converter using GAMESS output, and it matches my modified XML file from QP2.

However, applying the cusp corrections leads to incorrect results:
-379.338340 whereas the QP2 reference energy is -379.410416553535.

I also noticed that during the conversion it prints:
```
Done reading CIs!!
QMCGaussianParserBase::dump
```
which might explain why, although I set up the correct number of states, it still treats the wavefunction as a CI.

Is there a way I can tweak the converter so that QP2 CASSCF wavefunctions are correctly converted?

[QP2_CAS_4_4_modified.h5.txt](https://github.com/user-attachments/files/21724859/QP2_CAS_4_4_modified.h5.txt)

[QP2_CAS_4_4_unmodified.h5.txt](https://github.com/user-attachments/files/21724869/QP2_CAS_4_4_unmodified.h5.txt)

[qmcpack_from_gamess.wfj.xml.txt](https://github.com/user-attachments/files/21724884/qmcpack_from_gamess.wfj.xml.txt)

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