mirror of https://github.com/QMCPACK/qmcpack.git
22 lines
1.0 KiB
ReStructuredText
22 lines
1.0 KiB
ReStructuredText
Example 8: 2x2x2 Diamond k-point symmetry
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In this example we will show how to run an AFQMC simulation that exploits k-point symmetry
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which is much more efficient that running in the supercell way discussed in the previous
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example. We will again look at the same 2x2x2 cell of diamond. We assume you have run the
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scf calculation in the previous example.
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Essentially all that changes in the integral generation step is that we pass the
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`-k/--kpoint` flag to `pyscf_to_afqmc.py`.
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.. code-block:: bash
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mpirun -n 8 /path/to/qmcpack/utils/afqmctools/bin/pyscf_to_afqmc.py -i ../07-diamond_2x2x2_supercell/scf.chk -o afqmc.h5 -t 1e-5 -v -a -k
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You will notice that now the Cholesky decomposition is done for each momentum transfer
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independently and the the form of the hamiltonian file has changed to be k-point dependent.
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Apart from these changes, running the AFQMC simulation proceeds as before, however you
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should see a significant performance boost relative to the supercell simulations,
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particularly on GPU machines.
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