Right then, i have a question set as part of an assignment, where i have to describe the 6-311G* basis set for water. In my notes for this module i have the following basis sets described as shown:

3-21G

O 1s 2s 2s' 2p_{x,y,z} 2p'_{x,y,z}

H 1s 1s'

6-31G*

O 1s 2s 2s' 2p_{x,y,z} 2p'_{x,y,z} 3d (six functions)

H 1s 1s'

I understand that the star is a polarisation function on the heavier atoms, corresponding to the addition of the 6 3d basis functions to oxygen.

For 6-311G* i read this as being a split valence triple zeta plus polarisation basis set. (6 Gaussians on Core electrons, then split 3, 1, 1, Gaussians on valence electrons).

I think that this should look like the following:

O 1s 2s 2s' 2s'' 2p_{x,y,z} 2p'_{x,y,z} 2p''_{x,y,z} 3d (i read somewhere that there are only 5 polarisation functions on 6-311G* on the net somewhere, maybe someone can confirm that).

H 1s 1s' 1s''

I'm hoping that someone can confirm that i have correctly calculated the shells for the 6-311G* basis set in this case.

Thanks

Sam