<div dir="ltr"><div><div>Dear experts & developers,<br><br></div>I am working on a monolayer transition-metal trichalcogenide semiconductor<br></div><div>with a vacuum of about 20 \AA in the z-direction and I am trying to get MLWF</div><div>for the same. However the code throws the following error saying that it is <br></div><div>unable to satisfy B1 with any of the first  12 shells. I try changing the search_shells</div><div>parameters in the .win file as suggested by the code which does not help. I try</div><div>changing the tolerance which also goes in vain. I request the experts and developers <br></div><div>in this forum to point out the probable reason(s) for the error. Help acknowledge</div><div>thankfully in advance.</div><div><br></div><div><br></div><div>                satya<br></div><div><br></div><div><div><div><br>                                ------------<br>                                K-POINT GRID<br>                                ------------<br>  <br>             Grid size = 11 x 11 x  1      Total points =  121<br><br>*---------------------------------- MAIN ------------------------------------*<br> |  Number of Wannier Functions               :                48             |<br> |  Number of input Bloch states              :                48             |<br> |  Output verbosity (1=low, 5=high)          :                 1             |<br> |  Timing Level (1=low, 5=high)              :                 1             |<br> |  Optimisation (0=memory, 3=speed)          :                 3             |<br> |  Length Unit                               :               Ang             |<br> |  Post-processing setup (write *.nnkp)      :                 F             |<br> |  Using Gamma-only branch of algorithms     :                 F             |<br> *----------------------------------------------------------------------------*<br> *------------------------------- WANNIERISE ---------------------------------*<br> |  Total number of iterations                :               100             |<br> |  Number of CG steps before reset           :                 5             |<br> |  Trial step length for line search         :             2.000             |<br> |  Convergence tolerence                     :         0.100E-09             |<br> |  Convergence window                        :                -1             |<br> |  Iterations between writing output         :                 1             |<br> |  Iterations between backing up to disk     :               100             |<br> |  Write r^2_nm to file                      :                 F             |<br> |  Write xyz WF centres to file              :                 F             |<br> |  Use guiding centre to control phases      :                 F             |<br> *----------------------------------------------------------------------------*<br> Time to read parameters        0.004 (sec)<br><br> *---------------------------------- K-MESH ----------------------------------*<br> +----------------------------------------------------------------------------+<br> |                    Distance to Nearest-Neighbour Shells                    |<br> |                    ------------------------------------                    |<br> |          Shell             Distance (Ang^-1)          Multiplicity         |<br> |          -----             -----------------          ------------         |<br> |             1                   0.096882                      2            |<br> |             2                   0.096887                      4            |<br> |             3                   0.167807                      4            |<br> |             4                   0.167815                      2            |<br> |             5                   0.193764                      2            |<br> |             6                   0.193773                      4            |<br> |             7                   0.256327                      4            |<br> |             8                   0.256332                      4            |<br> |             9                   0.256341                      4            |<br> |            10                   0.279157                      2            |<br> |            11                   0.290645                      2            |<br> |            12                   0.290660                      4            |<br> +----------------------------------------------------------------------------+<br> | The b-vectors are chosen automatically                                     |<br> | SVD found small singular value, Rejecting this shell and trying the next   |<br> | SVD found small singular value, Rejecting this shell and trying the next   |<br> | SVD found small singular value, Rejecting this shell and trying the next   |<br> | SVD found small singular value, Rejecting this shell and trying the next   |<br> | SVD found small singular value, Rejecting this shell and trying the next   |<br>  <br> Unable to satisfy B1 with any of the first  12 shells<br> Your cell might be very long, or you may have an irregular MP grid<br> Try increasing the parameter search_shells in the win file (default=12)<br>  <br> Exiting.......<br> kmesh_get_automatic<br><br clear="all"><br>-- <br></div><div>Satyananda Chabungbam  <br></div><div>PostDoc Fellow</div><div>Harish-Chandra Research Institute</div><div>Allahabad-211019</div><div>India<br></div><div><div class="gmail_signature"><div dir="ltr"><span style="color:rgb(0,0,0)"><span style="background-color:rgb(153,0,255)"><span></span></span></span><br></div></div>
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