Posted by Roser on March 10, 2015 at 10:07:03:
Hello,
I was doing CASPT2 calculations and I saw that an iterative procedure is needed, but I don't understand why. CASPT2 method does not need iterations.
I have read in the manual (section 10.5 Excited states/CASPT2): "Of course, the complete Hˆ0 is used to solve the CASPT2 equations, which is why an iterative procedure is needed."
I had previously problems on the convergence and I would like to understand these iterations.
Thank you!
Roser