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Can not optimize geometry in MP2/aug-cc-pVDZ

Alexander Vasyanin
avasyanin@gmail.com

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
    2  E=     -727.7926962929  GMAX=   0.0001120  GRMS=   0.0000170
    3  E=     -727.7926963478  GMAX=   0.0001410  GRMS=   0.0000230
    4  E=     -727.7926963300  GMAX=   0.0001064  GRMS=   0.0000191
    5  E=     -727.7926963359  GMAX=   0.0000947  GRMS=   0.0000164
    6  E=     -727.7926963183  GMAX=   0.0000374  GRMS=   0.0000059
    7  E=     -727.7926963183  GMAX=   0.0000374  GRMS=   0.0000059
    8  E=     -727.7926963427  GMAX=   0.0000564  GRMS=   0.0000109
    9  E=     -727.7926821007  GMAX=   0.0022164  GRMS=   0.0003298
   10  E=     -727.7926963076  GMAX=   0.0001419  GRMS=   0.0000216
   11  E=     -727.7926963186  GMAX=   0.0000727  GRMS=   0.0000111
   12  E=     -727.7926963017  GMAX=   0.0001004  GRMS=   0.0000204
   13  E=     -727.7926963017  GMAX=   0.0001004  GRMS=   0.0000204
   14  E=     -727.7926963256  GMAX=   0.0000705  GRMS=   0.0000113
   15  E=     -727.7926963045  GMAX=   0.0001233  GRMS=   0.0000208
   16  E=     -727.7926963005  GMAX=   0.0000897  GRMS=   0.0000190
   17  E=     -727.7926963306  GMAX=   0.0001289  GRMS=   0.0000226
   18  E=     -727.7926963143  GMAX=   0.0000295  GRMS=   0.0000066
   19  E=     -727.7926963143  GMAX=   0.0000295  GRMS=   0.0000066
   20  E=     -727.7926963311  GMAX=   0.0000623  GRMS=   0.0000102
   21  E=     -727.7926960335  GMAX=   0.0002230  GRMS=   0.0000479
   22  E=     -727.7926963305  GMAX=   0.0000966  GRMS=   0.0000163
   23  E=     -727.7926963281  GMAX=   0.0000657  GRMS=   0.0000119
   24  E=     -727.7926963216  GMAX=   0.0001480  GRMS=   0.0000286
   25  E=     -727.7926963216  GMAX=   0.0001480  GRMS=   0.0000286
   26  E=     -727.7926963217  GMAX=   0.0000691  GRMS=   0.0000123
   27  E=     -727.7926963181  GMAX=   0.0000618  GRMS=   0.0000099
   28  E=     -727.7926961166  GMAX=   0.0001413  GRMS=   0.0000266
   29  E=     -727.7926962196  GMAX=   0.0000940  GRMS=   0.0000245
   30  E=     -727.7926963158  GMAX=   0.0000997  GRMS=   0.0000160
   31  E=     -727.7926963158  GMAX=   0.0000997  GRMS=   0.0000160
   32  E=     -727.7926963209  GMAX=   0.0001290  GRMS=   0.0000192
   33  E=     -727.7926963169  GMAX=   0.0000520  GRMS=   0.0000103
   34  E=     -727.7926963562  GMAX=   0.0001067  GRMS=   0.0000186
   35  E=     -727.7926963414  GMAX=   0.0000815  GRMS=   0.0000132

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!

This message contains the 3 kb attachment
[ 1_1.inp ] Input file which I can not optimize

[ This message was edited on Mon Feb 9 '15 at 7:47pm by the author ]

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