[Pw_forum] Tb09-MetaGGA convergence problem

[plgong]

Dear pwscf_user,
    Recently, I used  the tb09 (Meta-GGA) in the version of QE5.1.2, but it aways did not converge.
The error is like, 
     'Error in routine cdiaghg (23):
     eigenvectors failed to converge'

I have performed too much tests on Ecutoff, k_points, degauss, as well as reduce mixing.  What should I do?


My input file is,

&CONTROL
                 calculation = 'scf' ,
                restart_mode = 'from_scratch' ,
                      outdir = './tmp' ,
                  pseudo_dir = './' ,
verbosity='high',
                      prefix = 'graphene' ,
 /
 &SYSTEM
                       ibrav =0,
                         nat = 2
                        ntyp = 1,
celldm(1)=1.89,
ecutwfc= 60
input_dft='tb09'
                       nosym = .false. ,
                  tot_charge = 0.000000,
                 occupations = 'fixed', nbnd=24
 /
 &ELECTRONS
                    conv_thr = 1.D-7 ,
                 mixing_mode = 'plain' ,
                 mixing_beta = 0.1D0 , mixing_ndim=12
             diagonalization = 'cg' ,
 /
 &IONS
                ion_dynamics = 'bfgs' ,
           pot_extrapolation = 'second_order' ,
           wfc_extrapolation = 'second_order' ,
/
ATOMIC_SPECIES
    Si   12.01000 Si.pz-vbc.UPF
K_POINTS automatic
12 12 12 0 0 0
CELL_PARAMETERS
       0.000000000000000       2.715350000000000       2.715350000000000
       2.715350000000000      -0.000000000000001       2.715350000000000
       2.715350000000000       2.715349999999999      -0.000000000000000
ATOMIC_POSITIONS (crystal)
 Si   0.0000000000000000   0.0000000000000000   0.0000000000000000
 Si   0.2500000000000000   1.2500000000000002   0.2500000000000001



PL Gong
--

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Addr: Institute of Solid State Physics, Chinese Academy of 
Sciences, Hefei, Anhui 230031, China
Tel: +86-551-65591591(office), 18756086113(cell phone)
Email: plgong at theory.issp.ac.cn
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