<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: style=" font-size:="" 12pt;="" color:="" #000000"=""><div><style>/*<![CDATA[*/p {
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/*]]>*/</style></div><div data-marker="__QUOTED_TEXT__"><div style="font-family:'arial' , 'helvetica' , sans-serif"><div></div><div><div style="font-family:'arial' , 'helvetica' , sans-serif"><br><div>Hello everyone,<br></div><br><div> Does Thomas-Fermi screening reduces the Friedel oscillations ?<br></div><br><div> Because in R. M. Martin's book of "Electronic Structure, Basic Theory and Practical Methods" in the chapter 5, section 5.1 , subsection "Hatree-Fock approximation" , it is mentioned, that the velocity at the Fermi surface (d epsilon/ dk) is divergent. This divergence can be avoided by screening the Coulomb interaction. And Thoms-Fermi screening is one of the screening model.<br></div><br><div> Wheres, in the previous subsection of "Density matrix", Friedel oscillation is mentioned to be due to the sharp variation in the derivative of the Fermi function. <br></div><br><div> I am curious about it because I am doing Quantum Espresso calculation for a supercell containing two different type of atoms.<p class="western" style="margin:0px;line-height:100%"><span style="color:#000000"><span style="font-family:'courier new' , serif"><span style="font-size:small"><br></span></span></span></p></div><div>I am sorry if I have confused between two different effects.<br></div><br><div>Thanking you,<br></div><div>Best regards,<br></div><div>Krishnendu<br></div></div></div></div><br></div></div>
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