Effective Medium Theory (EMT) model driver based on the EMT implementation in ASAP (https://wiki.fysik.dtu.dk/asap).

Effective Medium Theory is a many-body potential of the same class as Embedded Atom Method, Finnis-Sinclair etc.  The main term in the energy per atom is the local density of atoms.

The functional form implemented here is that of Ref. 1.  The principles behind EMT are described in Refs. 2 and 3 (with 2 being the more detailed and 3 being the most pedagogical).  Be aware that the functional form and even some of the principles have changed since refs 2 and 3.  EMT can be considered the last step of a series of approximations starting with Density Functional Theory, see Ref 4.

These files are based on Asap version 3.11.5.


REFERENCES:

[1] Jacobsen, K. W., Stoltze, P., & Nørskov, J.: "A semi-empirical effective medium theory for metals and alloys". Surf. Sci. 366, 394–402  (1996).

[2] Jacobsen, K. W., Nørskov, J., & Puska, M.: "Interatomic interactions in the effective-medium theory". Phys. Rev. B 35, 7423–7442 (1987).

[3] Jacobsen, K. W.: "Bonding in Metallic Systems: An Effective-Medium Approach".  Comments Cond. Mat. Phys. 14, 129-161 (1988).

[4] Chetty, N., Stokbro, K., Jacobsen, K. W., & Nørskov, J.: "Ab initio potential for solids". Phys. Rev. B 46, 3798–3809 (1992).


HISTORY:

Changes in 004:

* Fixed a small memory leak.


Changes in 003:

* Updated to KIM API version 2.0.0.


Changes in 002:

* Bug fix: version 001 would crash with most tests/simulators due to an internal consistency test failing.

* Bug fix: version 001 reported a slightly too short cutoff, leading to small inaccuracies (probably only for Au).

* Bug fix: Memory leaks removed.

* Enhancement: version 002 now supports ghost atoms (parallel simulations, many other tests).

* Enhancement: version 002 now supports all neighbor list types, although the half lists give the best performance.


KNOWN ISSUES / BUGS:

* On-the-fly modifications of the parameters is not supported.  It should be implemented.