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Dear all,<div><br></div><div>I am doing phonon calculations at the Dirac K point of a graphene allotrope and I am getting two negative frequencies (almost degenerate). I need to confirm something regarding the units of the q-points. Should they be in terms of b1, b2 and b3, the reciprocal lattice vectors or in cartesian coordinates in terms of 2Pi/a? Is this written somewhere in the Guide...</div><div><br></div><div><br></div><div>Reagrds</div><div><br></div><div>Elie Moukaes</div><div>university of Nottingham</div><div>NG7 2RD</div><div>UK</div><div><br></div> </div></body>
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