Molpro 2012

Molpro is a software package that allows for high level wavefunction-based quantum-chemistry and is coupled to the metafalcon package by a text-based interface. Only CASSCF calculations have been performed and tested so far to work with metaFALCON.

Molpro is used, if the following information is provided in the meta-config.json file under the "molecular dynamics" keyword:

"interface": {
  "type": "molpro",
  "configure": {
    "nproc": 1
  }

It is possible to let Molpro run parallel calculations, if the "nproc" keyword is provided.

In order to allow the metaFALCON to construct the input textfile for Molpro in every dynamics step, two additional files are needed. The file head contains everything that should be in the Molpro input file before the molecular geometry. The file tail, on the other hand, contains everything to be placed after the molecular geometry.

For example, if the head file is

nosym;
geometry={

and the tail file is

}
basis=6-31g
{casscf
closed,13
occ,17
wf,30,1,0;state,2;
cpmcscf,grad,1.1,spin=0,record=5100.1
cpmcscf,grad,2.1,spin=0,record=5101.1}
force;samc,5100.1
force;samc,5101.1

the metaFALCON will build a Molpro input file for the calculation of the first two excited state energies and gradients on the CASSCF level in every dynamics step.

Note

In order to ensure that the active space does not change abruptly by the exchange of orbitals, a temporary wavefunction file should be saved in each Molpro run. Therefore, the first line of the head file should be:

file,2,temp.wfu

Note that an initial temp.wfu file has to be present before the start of the dynamics. Now the diab directive can be used to guarantee that the active space is consistent with the previous dynamics step. Insert the following lines into the casscf block after the wf directive:

orbital,2140.2
diab,2140.2