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  • Compilation problems

    1 Topics
    2 Posts
    C

    Dear @Julia-h2o ,

    You may find here instructions about compiling MPP version (please look
    at section 3):
    https://www.crystal.unito.it/include/manuals/CRYSTAL23_installation.html

  • Structure calculations, elasticity, etc.

    3 Topics
    6 Posts
    C

    Dear @Julia-h2o,

    We had a look at your files. We could not find any error at the end of 4br3clph.out This calculation was regular till the point where the file ends. Is it possible that you reached a wallclock limit on your cluster?
    Our suggestion for this kind of heavy calculations is to:

    run a OPTGEOM calculation to get the optimized structure;

    Starting from the optimized structure run a ELASTCON calculation (without PREOPTGEOM).

    Let us know how it goes.

  • Charge density, Compton Profile, CPHF

    1 Topics
    2 Posts
    C

    Dear @Lukas-jd,

    As you saw, the option you've been using to compute Compton profiles (CPs) does not work with f-type orbitals.

    Luckily, there is an alternative option in PROPERTIES that allows to compute CPs with f-type orbitals. It is the BIDIERD option (see Manual) that computes first the directional B(r) function and then Fourier transforms it into the corresponding CP.

    A possible syntax is like this:

    BIDIERD
    1 30000 0.001 0 1
    PROF
    60 0.1
    DIR
    1 0 0
    END
    END

    The numbers below the DIR keyword define the direction. In this case it is [100].

  • 1 Topics
    2 Posts
    C

    Dear @Julia-h2o,

    thanks for pointing out this omission in the tutorial. You can find the files attached (scan.d12, scan.out) and we hope they can be useful to you.

    elasticprop.out elasticprop.d12

  • General question on the application of Crystal to organic materials

    1 Topics
    2 Posts
    C

    Dear @Lukas-jd,

    Thank you for your interest in our software.
    CRYSTAL has been successfully applied to study organic crystals. Here are a few examples:

    https://pubs.acs.org/doi/full/10.1021/acs.jctc.6b00304 https://www.sciencedirect.com/science/article/pii/S0022286020310462?via%3Dihub https://pubs.rsc.org/en/content/articlelanding/2020/CE/D0CE01016B

  • Technical discussion on specific errors or problems

    1 Topics
    2 Posts
    C

    Dear @Lukas-jd,

    To remove the negative frequency you can try two procedures.

    Re-optimize the initial structure with a larger tolerance. You can make use of the EXTERNAL keyword using the f34 of the previous optimized structure. 
    For example:

    EXTERNAL
    OPTGEOM
    FULLOPTG
    TOLDEG
    0.00010
    TOLDEX
    0.0004
    TOLDEE
    11

    Run the SCAN-MODE to eliminate the negative frequency (see page 194 of Crysatl User's manual). To run the “scanmode” calculation: select the mode you want to eliminate; make an EXTERNAL, the f34 is the same used before; select the initial, final, and the step for the scan; run the calculation

    Example for the input:

    EXTERNAL
    FREQCALC
    SCANMODE
    1 -10 10 0.4 (number of the mode to eliminate, first step, last step, step displacement)
    2                    (sequence number of the modes selected)
    END
    END
    basis-set and etc

    after finishing the scanmode calculation, open each SCAN_ file and plot a graphical of mode x energy (see example on user's manual). vi. the minimal point should be your structure with minimal energy and no negative frequencies; vii. run an optimization making an EXTERNAL from the SCAN_file (that is the f34) of the minimal energy found before; viii. after, run the FREQCALC again.

    Now, it should not appear negative frequency.