Test input does not work

[fstein93]

Dear all,

After compiling the code, I tried the test case from the manual. Apparently, some keywords are outdated and thus not accepted anymore by NECI. Below, there is an updated file which does work, although I am not entirely that the tau search is turned on properly.

# comments are given like this
# simple N2 FCIQMC calculation
# for more complex FCIQMC variations , see the keywords for additional options
# such as the Hubbard model , transcorrelated options , or GAS-CI
title
  # read integrals from FCIDUMP
  system read
    electrons 6
    nonuniformrandexcits pchb delocalised
  endsys
  calc
    nmcyc 10000
    # for reproducibility
    seed 8
    totalWalkers 50000
    tau-values start user-defined 0.01
    #tau-search
    # use the initiator method
    truncinitiator
    addtoinitiator 3
    methods
      method vertex fcimc
    endmethods
  endcalc
  logging
    hdf5-pops
  endlog
end

[MaruSongMaru]

Hi, thank you for reporting the issue. You are right; the excitation generation and time step keywords in the input need to be updated. We will update them in our internal development branch first. Please be aware that it might take some time before these changes are reflected in the public branch.

Since tau-search is off by default, you need to enable it explicitly in the input for more efficient calculations. For example, you can change the input as shown below:

    ...
    tau-values \                                                                    
        start user-defined 0.01                                                     
    tau-search \                                                                    
        algorithm conventional \                                                    
        stop-condition no-change 1000
    ...