Alexander Vasyanin
avasyanin@gmail.com
I didn't solve the problem. Looks like it appears when diffusion functions added to the basis sets: with 6-311G* and cc-pVDZ it optimizes, but 6-311+G* and aug-cc-pVDZ both failed, oscillating with GMAX not less than 1E-4.
I think the problem is with some gradient artifacts so I also tried to set tighter values to NCONV (8) in addition to values for $MP2GRD recommended by Prof. Granovsky, but it breaks SCF convergence.
So I gave up...
On Mon Feb 9 '15 7:47pm, Alexander Vasyanin wrote
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>Dear All,
>I've got a problem with geometry optimization (see attached input file). DFT methods (B3LYP, PBE0) with the same input geometry converge fine, but MP2 fails to converge showing a progress like this:
>$ grep 'E=' 1.dat | cat -n
> 1 E= -727.7926962177 GMAX= 0.0001417 GRMS= 0.0000243
>I've tried to use symmetry (CS) to make calculation faster with IHREP=5 option, but it also didn't help to reach convergence even after 40 iterations.
>Is it possible to improve convergence (may be with some option in $MP2GRD)?
>Thanks in advance!