Molcas Forum

behe1986

Member

Registered: 2016-12-14

Posts: 2

Meaning of the #INFO block in InpOrb files

Hi there,

I am trying to  import the MO coefficients etc. provided on the ScfOrb, RasOrb, ... files
into a different QC package. The format of those InpOrb files are more or less self-explanatory.
So, first, thanks for providing such a plain and clean output.
I only struggle a bit with the #INFO block. For the water example in C2v symmetry
with cc-pVDZ basis set I get the following

#INFO
* SCF orbitals
       0       4       2
      11       7       4       2
      11       7       4       2

I have 2 questions in particular:

(1) What does 0 and 2 mean in the 0 4 2 line?

(2) Which of the 11 7 4 2 lines is the number of basis functions
      and which the number of orbitals? Of course, they are here the same
      as spherical Harmonics are used. How could I make them
      differ by using the Cartesian AO basis? Is there an input keyword?
      If that was never intended why are there then 2 lines?

Thanks for your time and support!

   Ben

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,085

Re: Meaning of the #INFO block in InpOrb files

(1) What does 0 and 2 mean in the 0 4 2 line?

0 is a "UHF" flag. If it's 1, the file will contain additional sections for "beta" orbitals, occupations and energies.

2 indicates the orbitals come from an RHF calculation:

0  -- Unknown origin of orbitals
1  -- Orbitals for Guessorb
2  -- Orbitals for closed shell HF
3  -- Orbitals for closed shell DFT
4  -- Orbitals for unrestricted HF
5  -- Orbitals for unrestricted DFT
6  -- Natural orbitals for unrestricted HF
7  -- Natural orbitals for unrestricted DFT
8  --

but I believe you can ignore it.

(2) Which of the 11 7 4 2 lines is the number of basis functions
      and which the number of orbitals? Of course, they are here the same
      as spherical Harmonics are used. How could I make them
      differ by using the Cartesian AO basis? Is there an input keyword?
      If that was never intended why are there then 2 lines?

The first is the basis functions, the second is the orbitals. I don't know if there's any way to get different numbers there. It doesn't seem using Cartesian basis functions (which you can get with Pople basis sets, or by using "Cartesian" in the native basis set format) or deleting orbitals actually causes different numbers.

behe1986

Member

Registered: 2016-12-14

Posts: 2

Re: Meaning of the #INFO block in InpOrb files

Dear Ignacio,

thanks for this prompt and clear answer!

Ben

valera

Administrator

Registered: 2015-11-03

Posts: 129

Re: Meaning of the #INFO block in InpOrb files

Ben,
in principle, the dimensions of coefficients can be different - e.g. due to deleted orbitals. First line - N of Basis functions, second - orbitals. But in practice - they are always the same (since SCF is the only program which can handle non square matrix of coefficients).