Ceilidh ... Re: Orbitals sorting with firefly

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Re: Orbitals sorting with firefly

On Sat Sep 27 '14 3:19am, alex wrote
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>Hello experienced ffly users and developers,
>I have encountered an (insolvable) problem when tried to sort my orbitals with J/IORDER. The details make the letter slightly longer as an average posts but should give the details.
>The goal of sorting is to get the sequence of orbitals:
>| 32 | 30 | 104 | 123 | 119 | 477 | 475 | orbital_id
>|116 | 117 | 118 | 119 | 120 | 121 | 122 | position

..
> $GUESS KDIAG=0 GUESS=MOREAD NORB=411 ASIS=.F. PRTMO=.T. NORDER=1
> IORDER(116)=-32 IORDER(117)=-30 IORDER(118)=-104
> IORDER(119)=123,119,120,121,122
> IORDER(121)=-477 IORDER(122)=-475
> $END
>Hmm, sorting of the active space is fine but # 120 is really lost.

First, you should understand that the command

IORDER(n) =a,b,c,d ....

fills the list of orbitals (starting at position n) with orbital numbers a,b,c,d , ... A minus sign before the orbital numbermeans that the two orbitals should be exchanged( e.g.

$guess IORDER(n)=-p $end

is the same as

$guess IORDER(n)=p IORDER(p)=n $end

Therefore, your command

IORDER(119)=123,119,120,121,122

is equivalent to:

IORDER(119)=123
IORDER(120)=119
IORDER(121)=120
IORDER(122)=121
IORDER(123)=122

The subsequent commands IORDER(121)=-477 IORDER(122)=-475 put orbital 477 in position 121 and orbital 475 in position 122. The orbital list then becomes:

123 | 119 | 477 | 475 | 122 orbital_id
119 | 120 | 121 | 122 | 123 position

you can see that orbital 120 is nowhere to be found, and that is the reason for the error you see.

your IORDER instructions should have been:

iorder(116)=-32
iorder(117)=-30
iorder(118)=-104
iorder(119)=-123
iorder(120)=-119
iorder(121)=-477
iorder(122)=-475

The manuals are your friends!

Pedro Silva

Sat Sep 27 '14 7:46pm

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