[Pw_forum] Changing Kinetic Energy cut-off

[Elliot Menkah]

Dear Giovanni,
I'm using working with CO adsorbing on Nickel and these are the PPs I'm
using: Ni.pbe-nd-rrkjus.UPF
           C.pbe-rrkjus.UPF
           O.pbe-rrkjus.UPF

Any more information with this added info would be appreciated.
Thank you.

Kind Regards
Elliot.
> Message: 4 Date: Mon, 6 Jul 2015 09:32:30 +0200 From: Giovanni Cantele
> <giovanni.cantele at spin.cnr.it> Subject: Re: [Pw_forum] Changing
> Kinetic Energy cut-off To: PWSCF Forum <pw_forum at pwscf.org>
> Message-ID: <B47EC227-F2EC-41BB-B2C7-25FCFAC9B711 at spin.cnr.it>
> Content-Type: text/plain; charset=us-ascii Dear Elliot, the answer
> could be: generally speaking, results should change not so much
> because energy differences are known to converge quite rapidly with
> respect to the cutoff . However, no answer could be given without more
> details. Indeed, the change of the properties with respect to
> ecutwfc/ecutrho strongly depends on the pseudo potential. So: which
> elements you are dealing with? Which type of pseudo potentials? Norm
> conserving or ultrasoft? In any case tests would be needed. Giovanni
>> > On 06 Jul 2015, at 00:22, Elliot Menkah <elliotsmenkah at yahoo.com> wrote:
>> > 
>> > Hello Everyone,
>> > How does or to what extent does changing your ecut along with ecutrho
>> > affect evaluation of results from computations?
>> > For instance if you used 60Ry to compute 'delta H' for reactants and you
>> > use 40Ry to compute 'delta H' for products.
>> > 
>> > Reduction to 40 Ry was because some jobs with 60 Ry took too long a time
>> > only not to converge even after 100 iterations.
>> > 
>> > Thank you.
>> > 
>> > Kind Regards,
>> > Elliot
>> > 
>> > -- 
>> > Elliot S. Menkah
>> > Research Student - Computational Chemistry/ Computational Material Science
>> > Theoretical and Computational Chemistry
>> > Dept. of Chemistry
>> > Kwame Nkrumah UNiversity of Sci. and Tech.
>> > Kumasi
>> > Ghana
>> > 
>> > Tel: +233 243-055-717
>> > 
>> > Alt Email: elliotsmenkah at gmail.com
>> >           elliotsmenkah at hotmail.com
>> > 


-- 
Elliot S. Menkah
Research Student - Computational Chemistry/ Computational Material Science
Theoretical and Computational Chemistry
Dept. of Chemistry
Kwame Nkrumah UNiversity of Sci. and Tech.
Kumasi
Ghana

Tel: +233 243-055-717

Alt Email: elliotsmenkah at gmail.com
           elliotsmenkah at hotmail.com