Molden output

[Ioannis Kerkines]

Hello,

Continuing some recent discussion on exporting orbitals to a file and be
able to manipulate them afterwards (with other programs), I would like to
make an observation which I do not understand.

The use of the "put,molden,filename" command dumps the orbitals (and some
other variables) to the "filename" in a certain order. I have trouble
understanding the ordering of the orbitals. For example, after running a
ROHF calculation and dump the orbitals, I get in the output:

 Molecular orbitals read from record     2130.2  Type=RHF/CANONICAL (state
1.1)
 Occupation numbers read from record     2130.2  Type=RHF/RHF (state 1.1)
 Orbital energies read from record       2130.2  Type=RHF/CANONICAL (state
1.1)
 Redundancy group numbers read from rec  2130.2  Type=RHF/RHF (state 1.1)

 DUMP ORBITAL  1.1 AS ORBITAL    1  occ=    2.0000  eig= -353.3128
GROUP=2
 DUMP ORBITAL  2.1 AS ORBITAL    2  occ=    2.0000  eig=  -44.3702
GROUP=2
 DUMP ORBITAL  4.1 AS ORBITAL    3  occ=    2.0000  eig=  -38.9334
GROUP=2
 DUMP ORBITAL  3.1 AS ORBITAL    4  occ=    2.0000  eig=  -38.9334
GROUP=2
 DUMP ORBITAL  5.1 AS ORBITAL    5  occ=    2.0000  eig=  -38.9333
GROUP=2
 DUMP ORBITAL  6.1 AS ORBITAL    6  occ=    2.0000  eig=  -11.3181
GROUP=2
 DUMP ORBITAL  7.1 AS ORBITAL    7  occ=    2.0000  eig=   -5.6464
GROUP=2
 DUMP ORBITAL  8.1 AS ORBITAL    8  occ=    2.0000  eig=   -3.8480
GROUP=2
 DUMP ORBITAL  9.1 AS ORBITAL    9  occ=    2.0000  eig=   -3.8479
GROUP=2
 DUMP ORBITAL 10.1 AS ORBITAL   10  occ=    2.0000  eig=   -3.8479
GROUP=2
 DUMP ORBITAL 11.1 AS ORBITAL   11  occ=    2.0000  eig=   -0.7913
GROUP=2
 DUMP ORBITAL 13.1 AS ORBITAL   12  occ=    2.0000  eig=   -0.7911
GROUP=2
 DUMP ORBITAL 12.1 AS ORBITAL   13  occ=    2.0000  eig=   -0.7911
GROUP=2
 DUMP ORBITAL 14.1 AS ORBITAL   14  occ=    2.0000  eig=   -0.7911
GROUP=2
 DUMP ORBITAL 15.1 AS ORBITAL   15  occ=    2.0000  eig=   -0.7911
GROUP=2
 DUMP ORBITAL 16.1 AS ORBITAL   16  occ=    2.0000  eig=   -0.7012
GROUP=2
 DUMP ORBITAL 17.1 AS ORBITAL   17  occ=    2.0000  eig=   -0.2992
GROUP=2
 DUMP ORBITAL 19.1 AS ORBITAL   18  occ=    1.0000  eig=   -0.4253
GROUP=1
 DUMP ORBITAL 18.1 AS ORBITAL   19  occ=    1.0000  eig=   -0.4253
GROUP=1

As one can see, orbitals are sorted according to their number, i.e. 1.1 is
orbital 1, 2.1 is orbital 2, etc., apart from degenerate orbitals (where
ordering changes).

When I repeat the same calculation with multi (but still a
single-refernce calculation), and then export the "canonical" MCSCF
orbitals, I get:

 Molecular orbitals read from record     2143.2  Type=MCSCF/CANONICAL
(state 1.1)
 Occupation numbers read from record     2143.2  Type=MCSCF/CANONICAL
(state 1.1)
 Orbital energies read from record       2143.2  Type=MCSCF/CANONICAL
(state 1.1)
 Redundancy group numbers read from rec  2143.2  Type=MCSCF/CANONICAL
(state 1.1)

 DUMP ORBITAL  1.1 AS ORBITAL    1  occ=    2.0000  eig= -353.3128
GROUP=*
 DUMP ORBITAL  2.1 AS ORBITAL    2  occ=    2.0000  eig=  -44.3702
GROUP=*
 DUMP ORBITAL  5.1 AS ORBITAL    3  occ=    2.0000  eig=  -38.9333
GROUP=*
 DUMP ORBITAL  6.1 AS ORBITAL    4  occ=    2.0000  eig=  -11.3181
GROUP=*
 DUMP ORBITAL  7.1 AS ORBITAL    5  occ=    2.0000  eig=   -5.6464
GROUP=*
 DUMP ORBITAL  8.1 AS ORBITAL    6  occ=    2.0000  eig=   -3.8480
GROUP=*
 DUMP ORBITAL 11.1 AS ORBITAL    7  occ=    2.0000  eig=   -0.7913
GROUP=*
 DUMP ORBITAL 14.1 AS ORBITAL    8  occ=    2.0000  eig=   -0.7911
GROUP=*
 DUMP ORBITAL 16.1 AS ORBITAL    9  occ=    2.0000  eig=   -0.7012
GROUP=*
 DUMP ORBITAL 17.1 AS ORBITAL   10  occ=    2.0000  eig=   -0.2992
GROUP=*
 DUMP ORBITAL  3.1 AS ORBITAL   11  occ=    2.0000  eig=  -38.9333
GROUP=*
 DUMP ORBITAL  9.1 AS ORBITAL   12  occ=    2.0000  eig=   -3.8479
GROUP=*
 DUMP ORBITAL 12.1 AS ORBITAL   13  occ=    2.0000  eig=   -0.7911
GROUP=*
 DUMP ORBITAL  4.1 AS ORBITAL   14  occ=    2.0000  eig=  -38.9333
GROUP=*
 DUMP ORBITAL 10.1 AS ORBITAL   15  occ=    2.0000  eig=   -3.8479
GROUP=*
 DUMP ORBITAL 13.1 AS ORBITAL   16  occ=    2.0000  eig=   -0.7911
GROUP=*
 DUMP ORBITAL 15.1 AS ORBITAL   17  occ=    2.0000  eig=   -0.7911
GROUP=*
 DUMP ORBITAL 18.1 AS ORBITAL   18  occ=    1.0000  eig=   -0.1243
GROUP=*
 DUMP ORBITAL 19.1 AS ORBITAL   19  occ=    1.0000  eig=   -0.1243
GROUP=*

Now the orbital ordering has completely changed. The same thing happens if
I export the natural MCSCF orbitals. Is there some ordering convention
here? 

If I remember correctly, Professor Knowles has mentioned that he
will make a patch available regarding the correct exporting of orbitals.
If this is some bug, perhaps it could also be taken into account.

Kind regards,
Ioannis