ABINIT Discussion Forums

What do you use as "spinat" value?

MHi, I am having troubles in downloading pseudopotentials, at least I can not download LDA Troulliers-Martins pseupotentials. What I need specifically is the Cobalt Troullier-Martins LDA pseupotential file (26co.pspnc). Can anyone help me?

Hi, following the spin tutotorial (part 1, bcc Fe), I get confused of some points and I wonder if anyone can help clear my mind about this: 1) "Spinat" input variable It is declared as "Gives the initial electronic spin-magnetisation for each atom, in unit of h-bar/2." wich seems...

Thanks for the tip!

Following previous post ( http://forum.abinit.org/viewtopic.php?f=8&t=1803 ) I wanted to do a 6x6x6 Monkhorst-Pack in this kind of spinel systems but I am not pretty sure of how to do it, I leave here the options: 1) ngkpt 6 6 6 2) Instead of kptrlatt 4 4 -4 -4 4 -4 -4 4 4 using kptrlatt 6 6 -6 ...

That seemed to work fine, thanks for the help

I did use that acell and rprim, my question was focussed on about xred because, as I said, writing down 14 entries as especied in m does not work. Taking another spinel example (cobalt ferrite: Fe2O4Co), I found a .cif that only specifies 3 asymetric atoms and used the brvltt -1 option nevertheless ...

Hello, I am trying to make same calculations (fist only the total energy) about spinel type structures (Prototype: Al2MgO4 (Spinel) Pearson Symbol: cF56, pace Group: Fd3m , Number: 227) and I took from m the primitive atoms (for the case SnMg2O4 where u = 0.375 see "First-principles study of ca...

Dear Torrent, Although the default value of diemac is 10^6, you can enter by hand the value of the dielectric constant in the input file using the input variable diemac. There is now way in principle that the program could adjust the value of the dielectric constant by itself (unless it looks the co...

Dear Torrent, May I have a comment of one of your statements: c) diemac is not exactly the dielectric constant; it is much more a adjustable parameter used for the preconditionning scheme of the SCF cycle. So, I'm not sure your implement will work in all cases. as abinit description of input variabl...

Dear Torrent, My name is Sergio Ferrari and I am physicist working in positron lifetime calculations in the Univesidad Nacional de La Plata. Answering to your question: for the moment I just the modification for my own usage. Thanks you very much for the tip of how to implement the modification more...

David
Thanks, that tip solved all. It is fair to say that this implementation greatly improves the lifetimes in semiconductors reaching to values very close to experimental ones. I stronlgy suggest to include this correction in a next version of ABINIT.

Hi, I am trying to modify the code so that the Boronsky-Niemenem positron enhacement factor (in the RPA limit, that is in the zero positron limit) includes the correction for screening of positron in semiconductors. So in the code of /src/56_xc/gammapositron.F90 in lines 178-179 Intead of: if (rs<=2...

Boris, According to myself experience, openmp and mpi are not the same. If I try to install abinit in the cluster i mentioned and use mpi I got a error message because the configure script can not find the mpi libraries. Consulting to the administrator, he said to me that mpi was not installed but o...

Really? I mean I am not root/administrator of the cluster and install such things usally requires admin privileges. That is why I am asking how to use openmp wich is the installed stuff there.

Dear abiniters,
I am trying to compile abinit in a cluster so I want to use the parallezation of abinit. The admistrator of the cluster said to me that the cluster has installed the openmp but not the mpi libraries. How do I set the configure options to this case?

Hi all, I am working in calculating positron lifetimes. I have a question about enhacement factors: does any of the options of ixcpositron includes the correction for screening of positron in semiconductors given by (1-1/ε_infinite) r_s^3 ; where ε_infinite is the high-frequency dielectric constant ...

Hi abiniters, I have the following problem, that should be easy to solve but I don't have inspiration right now. The problem is the folowing, I want run abinit in a supercell, lets say one 3x2x2, for example; in the original unit cell (cubic), I have an atomic position like e.g. 0 0.5 0.5; of course...

Hi, I was trying to run a calculation on a wurzite ZnO 2x2x2 supercell (positron lifetime) when I get the following message: irrzg : ERROR - irep= 16 not a divisor of nsym_used= 34 This usually indicates that the input symmetries do not form a group. Action : check the input symmetries carefully do ...

I have to point out that I decided to list all atoms of the unit cell (instead of the ones of the primitive cell) so to in a near future simulate vacancies or other defects

Dear Abiniters, I have been trying to make positron lifetime calculations in II-VI semiconductors which have a cubic diamond/zincblend structure. I haven't have any problem until I tried to make a 2x2x2 supercell calculus. The problem appeared in the least expected way: symfind : ERROR - The number ...

yes, dealing with 64 atoms will require a substantial amount of memory. I suspect that you compiled a 32bit Abinit - it's easy to check that afterwards on Linux with a file abinit ... it should return the ABI of the executable - 32 or 64bit. 32bit is limited to 2GB. You can setup a 64bit compilatio...

Hello Sergio, If you have a time consuming calculation, optimizing ecut - analyse the convergence of the plane wave cutoff - won't be a loss of time. If you're not the author of the pseudo, look in the accompanying files for ecut recommendations. And keep the test plain and simple with a ground sta...

I continue having this following error about memory:

memana : ERROR -
Test failed to allocate 1138.828 Mbytes
It is not worth to continue
Action : modify input variable to fit the available memory.
or increase limit on available memory.

The error message complains about PAW spheres overlapping ... seems fair to me as there is only a distance of 2.31 a.u. between a Zn and a Se. Looks very very small to me - there is something fishy in the atomic positions definition. But changing ecut or pawecutdg has a completely different effect ...