Export Wavefunctions to CHAMP¶

Since the ground and excited states have different symmetries, we handle them separately in CHAMP. We need to create two separate TREXIO files, one for each state.

Prepare State Directories¶

Copy the QP data directory COH2 for each state:

cp -r COH2 COH2_GS
cp -r COH2 COH2_ES

Extract States¶

Use qp_edit to isolate state 1 (Ground State) and state 2 (Excited State) in their respective directories:

qp set_file COH2_GS
qp edit --state=1

qp set_file COH2_ES
qp edit --state=2

Truncate Negligible Determinants¶

Remove determinants with very small coefficients to keep the QMC calculation efficient:

qp set_file COH2_GS
qp run truncate_wf  # Answer 1.d-10

qp set_file COH2_ES
qp run truncate_wf  # Answer 1.d-10

Export to TREXIO¶

Now create specific TREXIO files for each state. We start by copying the original file (to keep basis/geometry) and then update the determinants.

Ground State:

cp COH2.trexio COH2_GS.trexio
qp set_file COH2_GS
qp set trexio trexio_file COH2_GS.trexio
qp run export_trexio

Excited State:

cp COH2.trexio COH2_ES.trexio
qp set_file COH2_ES
qp set trexio trexio_file COH2_ES.trexio
qp run export_trexio

We now have COH2_GS.trexio and COH2_ES.trexio ready for CHAMP.