Questions tagged [relativistic]
Questions associated with relativistic concepts and methods in materials science.
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Software for quantum electrodynamics?
I've been reading some beginner books about quantum electrodynamics / quantum field theory (e.g. Feynman's QED book), and basically everything is done at the paper and pencil level.
I'm curious if ...
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What is the difference, if any, between an effective core potential (ECP) and a pseudopotential?
I've used these terms interchangeably for a while, but have noticed that in PySCF they are separate attributes.
Are there any crucial differences between an effective core potential (ECP) and a ...
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Calculating Te chemical shifts with Gaussian
I am trying to calculate chemical shifts for Tellurium in an organotellurium compound with Gaussian16 but the calculated values do not match experimental values at all. I know that NMR calculation ...
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How do scalar states with different multiplities make spin-forbidden reactions possible?
This question is related to How spin-orbit coupling makes spin-forbidden reactions possible? - Matter Modeling Stack Exchange
Even more importantly, [H,S2]=0 fails for multi-electron systems even ...
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How spin-orbit coupling makes spin-forbidden reactions possible?
My question is related to the Wikipedia page of spin-forbidden reactions https://en.wikipedia.org/wiki/Spin-forbidden_reactions
When a reaction converts a metal from a singlet to triplet state (or ...
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Scalar relativistic Calculation for pseudopotential
I am new to solid state calculation. I have a question about the pseudopotential in terms of the relativistic effect. In solid-state calculations, ultrasoft pseudopotential using PBE functionals are ...
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In which cases should SOC be included?
When dealing with 2D materials and monolayer families like : transition metal trihalides, TMDCs,...etc. In which cases SOC should be included in our calculations ?
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What are some of the advantages and disadvantages when using shape consistent pseudopotentials as compared to energy consistent pseduopotentials
From the literature as well as the answer to the question What is the meaning of energy-consistent and shape-consistent in the context of pseudopotentials? I can see that the key difference between ...
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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 ...
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For which elements should I include spin orbit coupling in Quantum ESPRESSO?
I'm trying to study a Yb-Ge-Sb compound and would like to include spin-orbit coupling (SOC). In Quantum ESPRESSO, this is done by including the following tags in the ...
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Theoretical origins of stereochemistry
What are the current theories of computational chemistry for studying homochirality (for example the phenomenon discussed here, here and in many other places)?
Electroweak chemistry has been developed ...
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How to generate relativistic pseudo-potential using Vanderbilt USPP that captures spin-orbit coupling?
I have used Vanderbilt USPP for generating a pseudopotential that does not include the spin-orbit term.
But I want to have the spin-orbit coupling term included in the pseudopotential, to do ...
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Converging the potential of a dilute binary alloy system using the Coherent Potential Approximation. What troubleshooting options could I take?
I'm trying to converge a dilute fcc alloy consisting of Cu and U, with the Uranium concentration at 0.01% and the lattice parameter of Cu, using Hubert Ebert's Spin Polarized Relativistic Korringa-...
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Spin–orbit interaction with DFT
I'm new to DFT.
Does the DFT take into account the spin-orbit interaction?
On the one hand, this is a relativistic effect, perhaps DFT does not take it into account.
However, on the other hand, I ...
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On mass polarization terms
In Jensen's Introduction to Computational Chemistry it says that the total non-relativistic Hamiltonian operator, transformed to the center of mass system, can be written, in atomic units, as
$$ \hat{...
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How to incorporate the effect of spin-orbit coupling in electronic structure calculation
Since the effect of spin-orbit coupling plays an important role in many transition metal complexes, what are the common methods to incorporate the effect of spin-orbit coupling?
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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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When should I include semi-core electrons in DFT calculations?
Many DFT codes use pseudopotentials (for the core electrons) and basis set functions (for the valence electrons) in order to solve the Schrodinger equation. This because simulates each electron ...
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Why were no correlation consistent basis sets for potassium contracted for a non-relativistic Hamiltonian?
On basis set exchange, the only correlation consistent (cc) basis sets for potassium, are relativistic (labelled by X2C). Very recently (I consider 2017 quite recent, because most Dunning basis sets ...
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