<div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div style="color: rgb(0, 0, 0); line-height: 1.7; font-family: Arial; font-size: 14px;"><div>Dear Paolo,</div><div>   Thank your for your reply. Now, I want to know how to apply Acoustic Sum Rule correction?  Thank you in advance!</div><div> </div><div>Best Regards!</div><div> </div><div>Yu <span class="typoRed" id="1426325470583.6965" evid="1426325470583.6965">Hailin</span><br><br></div><div id="divNeteaseMailCard"><br>At 2015-03-04 20:28:40, "Paolo <span class="typoRed" id="1426325470584.385" evid="1426325470584.385">Giannozzi</span>" <<a href="mailto:paolo.giannozzi@uniud.it">paolo.giannozzi@uniud.<span class="typoRed" id="1426325470584.6203" evid="1426325470584.6203">it</span></a>> wrote:>On Tue, 2015-03-03 at 17:24 +0800, ÓÚº£ÁÖ wrote:>>> 1. The frequences of <span class="typoRed" id="1426325470585.437" evid="1426325470585.437">freq</span> ( 1) ~<span class="typoRed" id="1426325470586.4087" evid="1426325470586.4087">freq</span> (    3)  should be zero, why>> there are not?>>http://www.quantum-espresso.org/faq/phonons/#7.2>>> 2. The hexagonal GaN is belong to C_6v (6mm) point group, why our>> result is C_3v (3m) point group as above shown?>>http://www.quantum-espresso.org/wp-content/uploads/Doc/pw_user_guide/node19.html#SECTION000600190000000000000>>Paolo>-- > Paolo <span class="typoRed" id="1426325470587.0632" evid="1426325470587.0632">Giannozzi</span>, Dept. Chemistry&Physics&Environment, > Univ. Udine, via <span class="typoRed" id="1426325470588.0395" evid="1426325470588.0395">delle</span> <span class="typoRed" id="1426325470589.2798" evid="1426325470589.2798">Scienze</span> 208, 33100 Udine, Italy> Phone +39-0432-558216, fax +39-0432-558222 >>_______________________________________________>Pw_forum mailing list><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a>>http://pwscf.org/mailman/listinfo/pw_forum</div></div></div><br><br><span title="neteasefooter"><span id="netease_mail_footer"></span></span>