# Re: Basis Input

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Posted by Matthias Mehring on February 12, 2009 at 15:24:44:

In Reply to: Re: Basis Input posted by Coen de Graaf on February 11, 2009 at 22:53:01:

To add some special augmentations to an implemented basis set one has to include the set using the inline format.
You have to look for the detailed exponents and coefficients of the basis set you want to apply, in your case the 6-31G*.
https://bse.pnl.gov/bse/portal
,there you'll find lots of basis sets for nearly all elements. Choose nitrogen and then the molcas format. You'll get something like this:

#################
!
! BASIS SET = 6-31+G*
!
* NITROGEN (11s,5p,1d) -> [4s,3p,1d]
* NITROGEN (1s,1p)
* NITROGEN (1d)
Basis set
NITROGEN / inline
7. 2
* S-type functions
11 4
4173.5110000
627.4579000
142.9021000
40.2343300
12.8202100
4.3904370
11.6263580
2.7162800
0.7722180
0.2120313
0.0639000
0.0018348 0.0000000 0.0000000 0.0000000
0.0139950 0.0000000 0.0000000 0.0000000
0.0685870 0.0000000 0.0000000 0.0000000
0.2322410 0.0000000 0.0000000 0.0000000
0.4690700 0.0000000 0.0000000 0.0000000
0.3604550 0.0000000 0.0000000 0.0000000
0.0000000 -0.1149610 0.0000000 0.0000000
0.0000000 -0.1691180 0.0000000 0.0000000
0.0000000 1.1458520 0.0000000 0.0000000
0.0000000 0.0000000 1.0000000 0.0000000
0.0000000 0.0000000 0.0000000 1.0000000
*p-type functions
...
#######################

If u include this format in your input, this allows to add some extra functions you are supposed to use. For this example, adding a diffuse s-functions will increase the number of primitves to 12, you additionally have to think about the contraction matrix of the coefficients, this changes from a 11x4 matrix to a 12x5 matrix in the easiest way. A possible contraction could be

NITROGEN / inline
7. 2
* S-type functions
12 5
with the matrix

0.0018348 0.0000000 0.0000000 0.0000000 0.0000000
0.0139950 0.0000000 0.0000000 0.0000000 0.0000000
0.0685870 0.0000000 0.0000000 0.0000000 0.0000000
0.2322410 0.0000000 0.0000000 0.0000000 0.0000000
0.4690700 0.0000000 0.0000000 0.0000000 0.0000000
0.3604550 0.0000000 0.0000000 0.0000000 0.0000000
0.0000000 -0.1149610 0.0000000 0.0000000 0.0000000
0.0000000 -0.1691180 0.0000000 0.0000000 0.0000000
0.0000000 1.1458520 0.0000000 0.0000000 0.0000000
0.0000000 0.0000000 1.0000000 0.0000000 0.0000000
0.0000000 0.0000000 0.0000000 1.0000000 0.0000000
0.0000000 0.0000000 0.0000000 0.0000000 1.0000000

Where the additional diffuse s-function is not contracted (see last column)

Also, you'll find lots of explanations concerning this in the manual.

Regards,
matthias

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