Solution LAB2 guanine 3: Difference between revisions
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Also, the following option needs to be used for charged systems : | Also, the following option needs to be used for charged systems : | ||
assume_isolated="mt" | assume_isolated="mt" | ||
Using ecutwfc=50 Ry and 35 au of cell size, | |||
E_tot(N) = | |||
E_tot(N-1) = -192.89782124 Ry | |||
giving | |||
Interestingly, one can run the same set of calculations also using different functionals, | |||
including GGAs (PBE), meta-GGAs (eg TPSS or SCAN), hybrids (PBE0), or HF itself. | |||
In order to do this, you can force e.g. the functional from input, by using: | |||
&SYSTEM | |||
[...] | |||
input_dft="PBE0" | |||
/ | |||
How do -eps_HOMO and delta-scf values compare ? | |||
Revision as of 10:33, 26 March 2021
- Back to the previous page: Electronic properties of isolated molecules#Exercise 3
For calculation of E(N-1) we need to set the following flags in the &SYSTEM namelist:
nspin=2 ! Note, now we have unpaired electrons: tot_charge=+1 ! charged system tot_magnetization=1 ! we need to set a total magnetisation
Also, the following option needs to be used for charged systems :
assume_isolated="mt"
Using ecutwfc=50 Ry and 35 au of cell size,
E_tot(N) = E_tot(N-1) = -192.89782124 Ry
giving
Interestingly, one can run the same set of calculations also using different functionals, including GGAs (PBE), meta-GGAs (eg TPSS or SCAN), hybrids (PBE0), or HF itself.
In order to do this, you can force e.g. the functional from input, by using:
&SYSTEM [...] input_dft="PBE0" /
How do -eps_HOMO and delta-scf values compare ?