Running ONIOM


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Hi Mhiranya,

Thank you for spotting this problem. Actually it turns out that the example was out-of-date. Judging by the presence of the "autosym" keyword on the first geometry this example must date back to a time when automatic symmetry detection was not the default behavior of the code. Hence in those days no symmetry would be used with the second geometry.

This behavior has been changed years ago. Now the code always tries to automatically detect symmetry, unless instructed otherwise. This leads it to find the incorrect D3D symmetry for the second geometry. So, now we need to explicitly intervene and lower the symmetry to get the correct behavior. Specifying the second geometry as

   H   -0.72023641     0.72023641    -1.16373235
H 0.98386124 0.26362482 -1.16373235
H -0.26362482 -0.98386124 -1.16373235
C 0.00000000 0.00000000 -0.76537515
H 0.72023641 -0.72023641 1.16373235
H -0.98386124 -0.26362482 1.16373235
H 0.26362482 0.98386124 1.16373235
C1 0.00000000 0.00000000 0.76537515

does just that. With this change the input will correctly.

I have updated the manual accordingly.

Best wishes, Huub