If you ran as you describe:

runsp_lapw -p -orb -ec 0.0001 -cc 0.0001 -i 60
runsp_lapw -p -orb -ec 0.0001 -cc 0.0001 -i 60

The first runsp_lapw should have ran the calculation from cycle 1 up to cycle 60. The second runsp_lapw should have then removed the broyd files and repeated the same calculation again from cycle 1 up to cycle 60.

Now, if you had did:

runsp_lapw -p -orb -ec 0.0001 -cc 0.0001 -i 60
runsp_lapw -p -orb -ec 0.0001 -cc 0.0001 -i 60 -NI

The first runsp_lapw should have ran the calculation from cycle 1 up to cycle 60. The second runsp_lapw should have then kept the broyd files (because of the -NI) and continued the calculation from cycle 61 up to cycle 120.

However, your new description that the energy and charge convergence are constant in every cycle is much clearer. So, I now don't think that increasing the maximum number of iterations will solve your problem.

Of the few mBJ calculations that I have ran, I don't remember ever having any problem just doing:

run[sp]_lapw ... -i 80 (with the default MSR1 in case.inm)

If I were to encounter a convergence problem, then I would restore my pre-mBJ calculation and try starting with a few iterations of PRATT and switch back to MSR1 [ https://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/msg07403.html ]:

run[sp]_lapw ... -i 15 (with PRATT in case.inm)
run[sp]_lapw ... -i 80 -NI (with MSR1 in case.inm)

If the mBJ instructions were written today, maybe PRATT would not be mentioned in the UG mBJ procedure.

I believe the PRATT part of the UG mBJ procedure was written back in the day when MSEC1 was the default (before MSR1 existed) [ http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg03783.html ]. I suspect that mBJ calculations starting with MSEC1 failed frequently, such that PRATT for a few iterations was the workaround to the MSEC1 problem.

There was one user in the past that reported that they had the same problem with a mBJ calculation, where the energy and charge convergence became constant in every cycle:


It looks like it might have been because they used too large of a mixing greed for PRATT. Since the thread of posts seem to stop, the user likely solved it by using a smaller (but not too small) PRATT mixing greed.

Unfortunately, you did not run the exact command that Prof. Marks sent and provide the output as it looks like it would have included information about the mixing parameters that were used during the calculation.

On 3/8/2016 9:37 AM, sikander Azam wrote:
Dear Laurence Marks <https://plus.google.com/u/0/115978139881852385108?prsrc=4> Thanks for your reply, Sir, actually we did mBJ+U calculations for parent compound. We got the convergence. Then we produce the vacancies in the parent compound, for that when we run the mBJ+U we get this problem i.e. the energy is not converged. So this is the only worry that why our calculations is not converging. Firstly we give 60 cycles, then 80, but this also didn't solve our problem i.e. we didnt got the convergence.

*Note:* By *grep :DIS *.scf* we get 0.21815 0.21815 0.21815 ..........20 times and by *grep :ENE *.scf* we get 0.5014 0.5014 .............................20 times

with best regard

On Tue, Mar 8, 2016 at 6:31 AM, Laurence Marks <l-ma...@northwestern.edu <mailto:l-ma...@northwestern.edu>> wrote:

    Please run the command below and post the result; it will provide
    some information about what is going on (although it may not
    answer everything). You can either run it in a linux shell (under
    bash) or paste it to a file (e.g. ~/bin/Check, $WIENROOT/Check or
    $WIENROOT/Check_lapw), do a "chmod a+x file" then just do "Check"
    (or whatever name you used).

    tail -n 100000 *.scf $1 | grep -e :ADIST -e :DIR -e :MV -e GREED
    -e :FRMS -e :ENE -e :CHARG -e PRATT \
    -e :DIS -e "MIXING SC" -e ":RANK" -e PLANE | \
    grep -v -e "with 1.0" -e scheme -e CONTRIBUTION | \
    tail -n 50

    On Tue, Mar 8, 2016 at 8:17 AM, sikander Azam
    <sikander.physi...@gmail.com <mailto:sikander.physi...@gmail.com>>

        Dear Gavin abin
        Thanks Sir for the reply, but I ran it for 60 cycle two times
        with commands
        runsp-lapw -p -orb -ec 0.0001 -cc 0.0001 -i 60

        On 8 Mar 2016 14:36, "Gavin Abo" <gs...@crimson.ua.edu
        <mailto:gs...@crimson.ua.edu>> wrote:

            How many cycles did the calculation run for and what did
            you set for the maximum number of iterations (i.e., the
            number that you set for the -i option)?

            If you did not use the -i option, just

            run_lapw or runsp_lapw

            The program will run up to 40 cycles by default.

            It is common for a mBJ calculation to not be able to reach
            converge within 40 cycles [1-3], which is why it suggests
            during the running of init_mbj that you increase the
            maximum number of interactions.  The example the init_mbj
            script gives is to set -i to 80:

            run_lapw -i 80 (or runsp_lapw -i 80)


            On 3/8/2016 3:51 AM, sikander Azam wrote:

                Dear all
                I am doing calculations using mBJ plus U, but when the
                calculations complete, I get that energy is not
                converged. But when I check the SCF file I get a
                constant value of 0.52341000 for energy convergence
                and 0.345680000 values for charge convergence.
                So I don't understand on the logic. please help me
                that what should I do. Should I continue with these
                calculations and find the properties or some one will
                give me some suggestions.
                Thanks in advance.

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