Increasing number of iterations
Just Got Here
10:12:25 AM PDT - Mon, Oct 5th 2015
So I am having issues increasing the number of iterations for my DFT calculation. I have tried maxiter (#) and iterations (#) but the output file still just gives me the 30 iterations which is default thus leading my convergence to a fail. My question is how do I fix this issue? is there another command that I am maybe not using? my input file is down here below.



start OsCl5O-3
echo
memory stack 2700 mb heap 200 mb global 2500 mb
charge -3
geometry noautosym units angstroms
Os 0.0000000  0.0000000  0.2099963

O  0.0000000  0.0000000  1.6000000

Cl 2.5855482  0.0000000  0.1642956

Cl 0.0000000 -2.5855482  0.1642956

Cl 0.0000000  0.0000000 -2.5226226

Cl 0.0000000  2.5855482  0.1642956

Cl -2.5855482  0.0000000 0.1642956
end
basis
Os library crenbl_ecp
Cl library crenbl_ecp
O library crenbl_ecp
end
ecp
Os library crenbl_ecp
Cl library crenbl_ecp
O library crenbl_ecp
end
scf
thresh 1.0e-05
tol2e 1.0e-08
Maxiter 300
triplet
rhf
end
task DFT

Forum Vet
11:00:25 AM PDT - Mon, Oct 5th 2015
Since you running a DFT task, the number of iterations is set in the DFT block
http://nwchemgit.github.io/index.php/Release66:Density_Functional_Theory_for_Molecules#ITERA...

start OsCl5O-3
echo
memory stack 2700 mb heap 200 mb global 2500 mb
charge -3
geometry noautosym units angstroms
 Os 0.0000000  0.0000000  0.2099963
 O  0.0000000  0.0000000  1.6000000
 Cl 2.5855482  0.0000000  0.1642956
 Cl 0.0000000 -2.5855482  0.1642956
 Cl 0.0000000  0.0000000 -2.5226226
 Cl 0.0000000  2.5855482  0.1642956
 Cl -2.5855482  0.0000000 0.1642956
end
basis
Os  library crenbl_ecp
Cl library crenbl_ecp
O  library crenbl_ecp
end
ecp
Os  library crenbl_ecp
Cl  library crenbl_ecp
O  library crenbl_ecp
end
scf
tol2e 1.0e-12
maxiter 300
triplet
rhf
end
# DFT block
dft
 maxiter 999
 mult 3
 tolerances acccoul 12
 convergence energy 1d-7
end
task DFT

Forum Vet
12:28:06 AM PDT - Tue, Oct 13th 2015
Yes, the calculation using the input prepared by Dr. Edoapra works, which requires 257 steps to converge.
A sequential run gives 
    Total DFT energy =     -181.256727471069

     One electron energy =     -836.262507968341

          Coulomb energy =      431.344711790476

   Exchange-Corr. energy =      -27.912812483271

Nuclear repulsion energy =      251.573881190067



Numeric. integr. density =       59.999995342134
...
moments of inertia (a.u.)
------------------

       2653.892412861391           0.000000000000           0.000000000000

          0.000000000000        2653.892412861391           0.000000000000

          0.000000000000           0.000000000000        3339.214285686515

    Total iterative time =    493.0s
...

 Are these reasonable?


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