Step: 129

The point group of the benzene results to D_6h , because n was 6. If you came to another result, pursue again carefully each of the decisions of the last two training steps on the basis the determination algorithm (you can use the back button of your browsers).
They see that with the benzene except the symmetry elements still available S determined above ₆ , i, s _v ⁽¹⁾ , s _v ⁽²⁾ , s _v ⁽³⁾ , s _d ⁽¹⁾ , s _d ⁽²⁾ , s _d ⁽³⁾ were not necessary for the determination of the point group. The determination algorithm simplifies thus the determination of the point group substantially.

Now the point group of the staggered ethane is to be determined.

1. Type of the axis of rotation:
Decide, into which part of the algorithm we arrive by the answer of this question!

Compare now with the training step 130 !