Hi all,
In the course of some benchmarking, I have faced with an unexpected and non-trivial issue when re-calculating the RI-MP2 energy of an optimized (at the same RI-MP2 level !) structure. After carring out a typical optimization with jobex -statpt -level mp2 -ri , I took the last (and optimized) structure with t2x -c and prepared a single-point calculation input at (exactly) the same level using define (for the dscf) and rimp2prep (for the rimp2). Surprisingly, the dscf energy of this single-point calculation was quite different from that obtained in the last step of the optimization (-2439.3820282307 versus -2439.546401018 hartrees). I guess that I must be doing something wrong, but I really do not know what it could be...Any solution, please?
Thank you very much in advance