Molcas Forum

stanistr

Member

Registered: 2021-05-12

Posts: 3

Asking for more Roots than mxroot=600?

Hi everyone,

I was wondering if there is an easy way to ask for more than 600 roots in a RASSCF calculation?

I tried asking for 1000 state-average "CIROOT 1000 1000 1" but received the error:

 Error: number of roots exceeds maximum
 NROOTS =                  1000
 MXROOT =                   600
--- Stop Module: rasscf at Sat May  8 12:27:40 2021 /rc=-6 ---

.########################.
.# Non-zero return code #.
.########################.

Is there an easy way to change this MXROOT setting or do I need to alter the source code and re-make/compile (I'm trying to avoid this if possible)?

Any help or advice would be really appreciated.

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,079

Re: Asking for more Roots than mxroot=600?

I'm afraid you'd have to recompile.

stanistr

Member

Registered: 2021-05-12

Posts: 3

Re: Asking for more Roots than mxroot=600?

Hi Ignacio,

Thank you for your reply. I recompiled like you said.

For anyone else who wants to alter the maximum roots that can be calculated, I changed the 'mxroot' parameter in the 'Molcas.fh' file in '/OpenMolcas/src/Include' DIR after I downloaded the newest version of OpenMolcas and then installed as normal. This seems to be working so far.