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5

Atomsk Creating surface based on Miller indices is tough work if it is not cubic lattice. for example $\langle011\rangle$ direction and $(011)$ plane normal in case of $c>a$ is not same. So, in case you are trying to create orthogonal simulation box, you may end up in a situation where orthogonal box is quite large or periodicity is not found. Dependency ...


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Constraint #16: Static linear response of the uniform electron gas This constraint is actually one of the 11 exact constraints that are also satisfied by the PBE GGA functional, as well as the TPSS Meta-GGA. If I'm understanding [1] correctly, the form of this constraint is: $$\lim_{k\to0}\gamma_x(y)=1+\frac{5}{9}y^2+\frac{73}{225}y^4-\frac{146}{3375}y^6+\...


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The Atomic Simulation Environment can generate surfaces and run LAMMPS.


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Coupled Cluster and MBPT methods The basis for this answer is the Brueckner-Goldstone linked-diagram theorem which applies to many-body perturbation theory (MBPT) and coupled-cluster methods. The original papers by Bruckner (1955) and Goldstrone (1957) are given in my answer explaining what about size-extensivity means. The most important part to remember is ...


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Configuration Interaction (CI) A good explanation of size consistency/extensivity for CI is given in Chapter 4, section 6 [1], though note that they describe both properties as forms of size consistency. This answer mostly focuses on truncated CI, but its helpful to contrast its behavior with Full CI. Full CI is size consistent and size extensive; this makes ...


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