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DanielRounds

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Registered: 2018-05-23

Posts: 2

What is effective core potential methods?

Quantum chemistry is a branch of chemistry it applies quantum mechanics.It also known as molecular quantum mechanics.it is used for theoretical study of chemical systems.I visitedThesis writing serviceto know more about this topic.I herd the term effective core potential method related to quantum chemistry.I need to know the detailed explanation of this term.It is an approximation method used for discarding core orbitals.

Last edited by DanielRounds (2018-07-17 11:22:05)

sobereva

Tian Lu (Multiwfn developer)

From: Beijing

Registered: 2017-09-11

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Re: What is effective core potential methods?

Effective core potential (ECP) method defines a single electron potential, which exerts on valence electrons. This potential represents Coulomb attractive interaction between nuclear charges and valence electrons as well as repulsive interaction between core electrons and valence electrons. The parameter of the potential is often optimized by minimizing the difference of wavefunction or energy of all-electron calculation with that of ECP calculation. When ECP is employed, the computational cost could be significantly lowered compared to all-electrons calculation if there are many heavy atoms in the system. In addition, if relativistic effect was taken into account when the ECP parameter was fitted, scalar relativistic effect can be effectively represented when ECP is used in your calculation.

ECP is a very important technique for studying very heavy atoms. In quantum chemistry calculation, ECP is often employed for the elements later than the fourth rows in the periodic table.

More information about ECP can be found in DOI: 10.1002/wcms.28.