Dear Krishnendu,
the group velocity of an electron associated to a given band is
related to the derivative of the energy band w.r.t. the k-vector, which
is roughly proportional to band-width and lattice parameters which for
valence electrons do not depend strongly on the elements involved.
Assuming a simple dispersion like e(k) = -A*cos(k*a) -> v_g =
1/\hbar d e(k)/ d k = A a/ \hbar * sen(k*a)
so max v_g ~ A a / \hbar . if you take A ~ 5 eV and a ~ 5 \AA,
then max v_g ~ 3 10^7 m/s ~ 0.1 c
The behavior of the electrons close to the nuclei is of course
affected by relativistic effects for heavy elements, this is why one
should use relativistic pseudopotentials.
stefano
On 07/11/24 06:57, KRISHNENDU MUKHERJEE via users wrote:
Hello everyone,
Does the valence electrons (those electrons for which the wave
function is solved in Quantum Espresso) have non-relativistic speed ?
Thanking you,
Regards,
Krishnendu
_______________________________________________
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
_______________________________________________
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
