[Pw_forum] slab Ewald sum quantum espresso

[Oliviero Andreussi]

Dear Niels,

I am probably not the most suited to answer and, probably, the best 
mailing list to address this problem is the qe-developers one 
(q-e-developers at qe-forge.org). Moreover, it is not fully clear to me 
what you are planning to do (Ewald sum is only part of the electrostatic 
energy of the system, the other relevant one being the Hartree term, are 
you proposing a 2D version of that as well? or you include all 
electrostatic under the Ewald label? or you refer to something else...), 
so I apologize in advance if I got it wrong.

On my side, I have been working with reduced dimensionality systems and 
I have been (recently) implementing the 2D and 1D version of the 
Martyna-Tuckermann correction schemes (Mináry, P., Tuckerman, M. E., 
Pihakari, K. A., & Martyna, G. J. (2002) The Journal of Chemical 
Physics, 116(13), 5351–5362. http://doi.org/10.1063/1.1453397). I 
haven't committed anything yet, as I am still debugging the code, but I 
plan to make it public as soon as everything is sound.

On the other hand, I have also implemented some quadratic correction 
schemes (for 0D and 2D systems, some details in Andreussi, O., & 
Marzari, N. (2014). Electrostatics of solvated systems in periodic 
boundary conditions. Physical Review B, 90(24), 245101. 
http://doi.org/10.1103/PhysRevB.90.245101) inside the Environ module 
that we are developing, www.quantum-environment.org.

I guess any new fully working (and maintained) feature would be a plus 
for the code, even if there are already similar things under development.

Best,

Oliviero Andreussi

Senior Postdoctoral Associate

École Polytechnique Fédérale de Lausanne (EPFL) and

Università della Svizzera Italiana (USI) of Lugano

Switzerland



On 10/12/2015 02:32 PM, Niels R. Walet wrote:
> The title says it all--Has anyone ever tried to replace the 3D Ewald sum
> in quantum espresso with a quasi-2D slab Ewald sum (yes, I know, that
> would not be general, and requires on using certain type of crystal unit
> cells).
> If it has bot been done, am I daft to think it should not be a total
> mistake to implement it?
> Niels
>