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** Re^3: EDSHFT parameter in XMCQDPT2 calculations **
Alexei Popov

alexei.a.popov@gmail.com

Dear Evgeniy,> OK, what difference in general one would expect

> for the transition energy calculated with and without

> the recommended EDSCHFT, which is 0.02. In my case I get the

> difference of about 0.1 eV. Is that acceptable/normal in general?

In most cases QDPT calculations are plagued by intruders so that

the difference up to several Hartrees could be expected while

comparing computations with and without ISA shift.

The difference of 0.1 eV is in general acceptable and likely

indicates that there are no significant intruder states-related

problems in your calculations.

--Alexei

Fri Dec 4 '15 11:37pm

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