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Thomas Pijper
thomaspijper@hotmail.com

Judging from the error message you've encountered your projection instructions are most likely still not correct. Let me explain a bit further what is needed for projection:

- A $VEC group containing orbitals obtained with the smaller basis.
- A $GUESS group a) which instructs Firefly to read in the $VEC group. NORB specifies the number of orbitals to read in (typically all orbitals in $VEC); b) which contains the EXTRA=.T. directive which tells Firefly that you're going to project onto a larger basis.
- A $BASIS group which specifies the larger basis.
- The $EXTRA NEXTRA(1)= instruction which tells Firefly atom by atom how many additional functions the larger basis contains for that atom. Indeed, in your case this is 6 for each 'C' and 'N' atom and 3 for each 'H' atom. (Note: this is always 6 for each d function, 10 for each f function, etc. regardless of the setting of the D5 keyword.)

As for the statement on page 68, this applies only to the N-311G/MC basis as well as the basis mentioned after that. This does not include N-31G. From the manual:

The following sets in Firefly should be used with Cartesian d functions:

STO-NG, N-21G, N-31G, SBKJC, HW, DH, DZV, TZV, MINI, and MIDI

As spherical functions are disabled by default, one does not have to specify
anything special when augmenting these basis sets with d functions.

Hope this helps.


Kind regards,
Thom


On Tue Apr 8 '14 8:41pm, pejer wrote
------------------------------------
>I've tried to specify only the $BASIS and it works. But then, I've got error message:

> INITIAL GUESS ORBITALS GENERATED BY MOREAD   ROUTINE.

> CONDITION NUMBER OF OVERLAP MATRIX IS:  4.29731159E+00
> *** ERROR READING THE MO COEFFICIENTS AT   1  89
>     THE INPUT VALUES WERE   2   1

>Does it means that i was wrong in defining NORB? I put the NORB from "NUMBER OF OCCUPIED ORBITALS" in output file of 6-31G run.

>For NEXTRA keyword, it means that I have to set "6" for every C and N atoms, and "3" for every H atom, right?

>I use spherical functions for both 6-31G and 6-31G(d,p) because of this statement : "Not using spherical functions for these sets can result in discrepancies in energies and/or poor SCF convergence"  (Firefly manual, page 68). I think I misunderstand this because "these" word means for several basis sets being mentioned.
>
>
>Best regards

[ This message was edited on Wed Apr 9 '14 at 0:17am by the author ]