[Wien] Vol optimization for BaRuO3

Oleg Rubel orubel at lakeheadu.ca
Wed Feb 25 22:05:43 CET 2015


It looks like the Etot vs Vol is a parabola upside down. The Bulk modules is negative. It indicates that there are more serious issues with the calculation than just plotting.

Oleg


> On Feb 25, 2015, at 15:28, delamora <delamora at unam.mx> wrote:
> 
> Thank for your reply
> Indeed there is no fit for the EOS2, Murnaghan, but for the Birch-Murnaghan there is a fit.
> What confused me was that for the simplest case; Na, the three equations are well fit.
> ********************************************
> 
> BaRuO3.outputeos
> Equation of state: EOS2 (PRB52,8064)        info           1
> a,b,c,d    -25949.930173      3630.427509    -28225.925163     73176.569689
> V0,B(GPa),BP,E0            NaN            NaN            NaN
> cubic lattice parameter:       NaN bohr =        NaN Ang
> 
> Equation of state: Murnaghan                info           5
> E=E0+[B*V/BP*(1/(BP-1)*(V0/V)**BP +1)-B*V0/(BP-1)]/14703.6
> Pressure=B/BP*((V0/V)**BP -1)
> V0,B(GPa),BP,E0            NaN            NaN            NaN               NaN
> cubic lattice parameter:       NaN bohr =        NaN Ang
>         vol       energy         de(EOS2)      de(Murnaghan)  Pressure(GPa)
>     390.4272   -25794.173431    -0.000730          NaN            NaN
>     368.7368   -25794.118027     0.000434          NaN            NaN
>     347.0462   -25794.018815    -0.000096          NaN            NaN
>     412.1175   -25794.204604     0.000543          NaN            NaN
>     433.8079   -25794.217951    -0.000151          NaN            NaN
>                  Sigma:          0.000458          NaN
> 
> Equation of state: Birch-Murnaghan                info           5
> E = E0 + 9/16*(B/14703.6)*V0*[(eta**2-1)**3*BP + (eta**2-1)**2*(6-4*eta**2)]
>  	  --> eta = (V0/V)**(1/3)
> Pressure = 3/2*B*(eta**7 - eta**5)*(1 + 3/4*(BP-4)*[eta**2 - 1])
> V0,B(GPa),BP,E0        74.4783    -14614.5174         5.9286     -25780.948961
> cubic lattice parameter:    4.2074 bohr =     2.2264 Ang
>         vol       energy         de(Birch-Murnaghan)  Pressure(GPa)
>     390.4272   -25794.173431    -0.001167               30.439
>     368.7368   -25794.118027     0.003237               51.446
>     347.0462   -25794.018815    -0.001325               77.903
>     412.1175   -25794.204604    -0.002076               13.683
>     433.8079   -25794.217951     0.001342                0.272
>                  Sigma:          0.001985
> 
> 
> 
> ________________________________________
> De: wien-bounces at zeus.theochem.tuwien.ac.at <wien-bounces at zeus.theochem.tuwien.ac.at> en nombre de Oleg Rubel <orubel at lakeheadu.ca>
> Enviado: miércoles, 25 de febrero de 2015 01:56 p. m.
> Para: A Mailing list for WIEN2k users
> Asunto: Re: [Wien] Vol optimization for BaRuO3
> 
> It might be useful to provide more information from "Optimize volume, c/a-ratio, …”
> Just include the whole page (list of scf files read, EOS fitting tables).
> 
> Oleg
> 
>> On Feb 25, 2015, at 14:22, delamora <delamora at unam.mx> wrote:
>> 
>> Dear Wien comunity,
>> 
>> I calculated BaRuO3
>> Cubic P (SG 221)
>> a=b=c=4A
>> Ba .5,.5,.5
>> Ru 0,0,0
>> O .5,0,0
>> I do an optimization with low quality RxK=7 Kpoints=100
>> Vol; 0,-5,-10,-15,-20
>> I try to plot Energy-Vol and I get a flat line above 0 with NaN,NaN...
>> I do the same witn Na and I get a nice plot.
>> I have the Wien2k 14.2 compiled with intel/Compiler/11.1/072/
>> BaRuO3 is a simple system which should not give problems!! but it is giving me lots.
>> 
>>        Thanks
>> 
>>                Pablo de la Mora
>> <Na-En-Vol.pdf><BaRuO3-En-Vol.pdf>_______________________________________________
>> Wien mailing list
>> Wien at zeus.theochem.tuwien.ac.at
>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>> SEARCH the MAILING-LIST at:  http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
> 
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:  http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:  http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html



More information about the Wien mailing list