Questions tagged [pseudopotentials]

Refers to the approximation of core electrons by effective potentials. Used in plane-wave and Gaussian based theories.

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14
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2answers
315 views

What are the types of pseudopotentials?

I would like to know what are the different types of pseudopotentials, the pro and cons, and what properties can/cannot be calculated with them?
22
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1answer
141 views

When do relativistic effects need to be explicitly included?

For many applications with heavy metals, pseudopotentials can be used to include some amount of relativistic effects. But for what sort of systems does it become necessary to actually use a ...
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2answers
1k views

What is the difference between Ultrasoft, ONCV and PAW Pseudopotentials? Which is better for a spin-orbit coupled calculation?

I am trying to do spin-orbit coupled calculations for various topological insulators. I have found papers using Quantum Espresso with ONCV pseudopotentials and papers using VASP with PAW ...
19
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2answers
212 views

Norm-Conserving or Ultrasoft, which pseudopotential to choose?

Ultrasoft pseudopotential (USPP), in general, requires a lower energy-cutoff to the plane waves when compared to Norm-Conserving ones (NC). On the other hand (at least with Quantum ESPRESSO) the ...
13
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2answers
351 views

When are atomic-orbital-basis (rather than plane-wave) methods appropriate in periodic DFT?

For example, GPAW supports both plane-wave and atomic-orbital basis methods. I know that atomic-orbital basis methods can have difficulty with electrons occupying vacancies for example, but what ...
11
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2answers
339 views

How to convert Unified Pseudopotential Format (UPF) into Ultrasoft Pseudopotential (USPP) format?

I am working on DFT code having plane wave along xy axis and bspline in z direction. For calculating the properties of TMD materials, spin orbit coupling must be included but i did not find fully ...
6
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1answer
105 views

What is the meaning of energy-consistent and shape-consistent in the context of pseudopotentials?

I am trying to use pseudopotentials to model scattering from heavy molecules. However, I am confused by some of the terminologies of pseudopotentials/ECPs: Norm-conserving according to Wikipedia and ...