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Dear xiaoqiqu97,
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<div class="">Users asking questions in this forum should sign with their full name and their affiliation.</div>
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<div class="">Regarding your question: matrix elements decay with distance, but typically do not go exactly to zero.</div>
<div class="">When using the matrix elements in other codes, these often can be required to have non-zero elements only up to a given distance. The flag you mention will set to zero any matrix element where the distance is larger that the value “dist_cutoff”
when performing the Wannier interpolation (so you can check the convergence of the computed quantities as a function of this distance, for instance).</div>
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<div class="">Best,</div>
<div class="">Giovanni Pizzi</div>
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-- <br class="">
Giovanni Pizzi<br class="">
Theory and Simulation of Materials and MARVEL, EPFL<br class="">
<a href="http://people.epfl.ch/giovanni.pizzi" class="">http://people.epfl.ch/giovanni.pizzi</a><br class="">
http://nccr-marvel.ch/en/people/profile/giovanni-pizzi</div>
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<div class="">On 16 Dec 2018, at 09:38, xiaoqiqu97 <<a href="mailto:xiaoqiqu97@gmail.com" class="">xiaoqiqu97@gmail.com</a>> wrote:</div>
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<div class="">Dear sir:</div>
<div class="">Recently, I learn about tutorial 14.</div>
<div class="">I am a beginer about wannier and nanotcad.</div>
<div class="">I can not understand about this:</div>
<div class="">the cutoff diatance:the largest distance between two WFs for which the Hamiltionian matrix element is retained and used. Units are Angstrom.</div>
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<div class="">Could you explain it in detail?</div>
<div class="">Thank for your help!</div>
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