I would like to share a new paper in JCTC very recently: pubs.acs.org/doi/10.1021/acs.jctc.8b00358

An Efficient Hartree–Fock Implementation Based on the Contraction of Integrals in the Primitive Basis

It looks very promising.]]>

I have just had a job crash on "spin case 19" after about 22 days (32000 minutes) of calculations to do spin cases 1-18:

I wonder if it's possible to make it so that we can save the results from spin cases 1-18, and then when we restart, just start with spin-case 19 immediately?

Also, I wonder if the energy contributions for each spin-case can be printed when the spin-case finishes?

The reason why is that I don't want to wait another 22 days to do spin-cases 1-18 all over again, and in the cases where there's only 19 spin-cases in total, then an estimate based on spin-cases 1-18 seems good enough. (of course ideally we'd do all 19 spin-cases, but if it means we have to restart from spin-case 1 and wait 22 days, we would rather just use the energy estimate coming from the first 18/19 spin cases).

Finally, is there an equation we can refer to in order to understand the different spin cases? I have looked at:

M. Kállay and J. Gauss (2008) Approximate treatment of higher excitations in coupled-cluster theory. II. Extension to general single-determinant reference functions and improved approaches for the canonical Hartree–Fock case. J. Chem. Phys. 129, pp. 144101, in the context of the notation in:

M. Kállay and J. Gauss (2005) Approximate treatment of higher excitations in coupled-cluster theory. J. Chem. Phys. 123, pp. 214105.

and:

Y. J. Bomble, J. F. Stanton, M. Kállay and J. Gauss (2005) Coupled cluster methods including non-iterative approximate quadruple excitation corrections. J. Chem. Phys. 123, pp. 054101.

I understand usually we only have 3 spin-cases and it becomes more spin-cases when we don't have enough RAM to do the 3 spin-cases fully, but what are the new spin-cases and how are they designed?

With best wishes!

Nike]]>

1) Highly-optimized, in-core, extremely memory economic, OpenMP-parallel closed-shell DF-CCSD(T) program.

2) Optimized closed-shell LNO-CCSD(T): ~20-30% less wall time, better OpenMP parallel scaling, 50-70% less minimum memory requirement, negligible disk I/O.

3) Reduced-scaling CIS, TD-HF, TDA, and TD-DFT approach.

4) Spin-component-scaled excited-state theories (SCS-CC2, SOS-CC2, SCS-ADC(2), SOS-ADC(2)), both conventional and reduced-scaling implementations.

5) New conventional/density fitting MCSCF program.

6) Local density fitting for open-shell SCF theories.

7) A couple of bugs have been fixed and the manual has been improved.

It is recommended for every user to upgrade to this version.]]>

Then I had the idea to use ORCA or Molpro interfaces to MRCC to compute orbitals and pass them to MRCC for post-HF stuff but the respective manuals state that only closed-shell molecules may be computed this way.

Thus my question: Is it possible to generate orbitals (e.g. with Molpro) and feed them to MRCC in standalone mode to be used in post-HF calculations? I feel like this should be possible.

Also, if this is indeed possible, could someone maybe explain how to do it?

I would greatly appreciate any help!

All the best, Benedikt]]>