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VMC → DMC Workflow

(Reference: tests/CI_test/DMC-TREXIO-water-DFT-jas2body_tau0.05)

This is the standard production workflow: optimize the wavefunction in VMC, then run DMC to get the final energy.

Steps

  1. VMC Optimization:

    • Optimize the wavefunction as described in VMC Optimization.
    • Save the optimized parameters (usually done automatically to jastrow_optimal and orbitals_optimal).

  2. VMC Walker Generation:

    • Run a short VMC calculation with the optimized wavefunction.
    • Set vmc_nconf_new to the desired number of walkers (e.g., 100 per core).
    • This generates mc_configs files.

  3. DMC Run:

    • Create a new input file (or modify the existing one).
    • Load the optimized Jastrow and orbitals.
    • Set mode = 'dmc_one_mpi1' (or similar DMC mode).
    • Configure the dmc module (time step tau, etrial).

Example Input (DMC Step)

load jastrow      jastrow_optimal
load orbitals     orbitals_optimal

%module blocking_dmc
    dmc_nstep     100
    dmc_nblk      200
    dmc_nconf     100
%endmodule

%module dmc
    tau           0.01
    etrial        -76.40  # From VMC
%endmodule