Molcas Forum

vkj

Member

Registered: 2019-04-10

Posts: 29

Potential energy of 1-el density with external charges

Dear developers,

I have a *Rasorb.* or *Pt2Orb.* file containing orbitals and occupation numbers.  I want to compute the potential energy (the Coulomb Interaction/Electrostatic Interaction) between this 1-el density and and external field represented by point charges in Xfield.

Is there a way to do it ?

I tried it with &seward using follwing input:

&SEWARD
 COORD=$MOLCAS_SUBMIT_DIR/../atoms.xyz
 BASIS=SIX-THREEONEGP
 BASDIR=$MOLCAS_SUBMIT_DIR/../
 XFIELD=$MOLCAS_SUBMIT_DIR/xfield.dat
 ONEOnly
 FILEorb=$MOLCAS_SUBMIT_DIR/../molcas.RasOrb.1
 ORBCon
 VECTors

But in this case I only orders of multipole terms.

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,085

Re: Potential energy of 1-el density with external charges

I believe you need to compute the electrostatic potential at the points where you have the charges (use EPOT instead of XFIELD), and do the product and sum yourself.