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<p>Dear QE users,</p>
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<p>I want to use QE to calculate photon dispersion by ph.x, but I face with a problem:</p>
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<div> Error in routine divide_class (1):</div>
<div> Wrong classes for C_3v</div>
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and my ph.x input file
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<div>&INPUTPH</div>
<div> outdir='/home/MS70/Clarence/cubr/phonon',</div>
<div> verbosity='low',</div>
<div> prefix = 'unit' ,</div>
<div> tr2_ph = 1.0d-14 ,</div>
<div> ldisp = .true. ,</div>
<div> fildyn = '/home/MS70/Clarence/cubr/phonon/unit.dyn' ,</div>
<div> fildrho ='cubr.drho' ,</div>
<div> nq1 = 8 ,</div>
<div> nq2 = 8 ,</div>
<div> nq3 = 1 ,</div>
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<div>Many thanks.</div>
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<div>LIANG Xiongyi<br>
City University of Hong Kong</div>
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