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LR-HF and SOPPA of BH molecule

Posted: 24 Oct 2014, 14:47
by jtravers70
Dear Dalton Users

I am using DALTON2013.4 to perform LR-HF calculations of BH(R=1.232 Å) with aug-cc-pVTZ basis. The triplet Pi state calculated by DALTION is 7.35 eV. it is very different from other programs, such as Gaussian, where a negative value (-1.63) is predicted. I thought this is related to the SCF instability of BH. but my questions is where is this 7.35 eV excitation energy from? Also,it seems some other excited states (singlet Pi, triplet Sigma+) agree reasonably well with exp and other computed data (EOM-CC). so, is there any way justify the computed results?
Also, if I perform SOPPA calculations for the triplet Pi state, I got a number about 7.35 eV, which I think is not reliable at all. Am i right?

Thank you!

Best wishes

john

Re: LR-HF and SOPPA of BH molecule

Posted: 24 Oct 2014, 14:54
by sauer
BH is multiconfigurational. Therefore neither HF nor SOPPA will be any good for this molecule. You should perform MCSCF calculations.

Good luck
Stephan