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--></style></head><body lang=JA link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Dear Paolo,</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>trigonal lattice (ibrav = 5) has same angles alpha = beta = gamma.</span></p><p class=MsoNormal><span lang=EN-US>However, only cos(gamma) or cosab is copied to celldm(4), as the source file (cell_base.f90, line211-240):</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US> IF ( celldm(1) == 0.D0 .and. a /= 0.D0 ) THEN</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> celldm(1) = a / bohr_radius_angs</span></p><p class=MsoNormal><span lang=EN-US> celldm(2) = b / a</span></p><p class=MsoNormal><span lang=EN-US> celldm(3) = c / a</span></p><p class=MsoNormal><span lang=EN-US> IF ( (ABS(cosab) > 1.0_dp) .OR. (ABS(cosac) > 1.0_dp) .OR. &</span></p><p class=MsoNormal><span lang=EN-US> (ABS(cosbc) > 1.0_dp) ) CALL errore ('cell_base_init',&</span></p><p class=MsoNormal><span lang=EN-US> 'incorrect values for cosab, cosac, cosbc',1)</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> IF ( ibrav == 14 ) THEN</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ! ... triclinic lattice</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> celldm(4) = cosbc</span></p><p class=MsoNormal><span lang=EN-US> celldm(5) = cosac</span></p><p class=MsoNormal><span lang=EN-US> celldm(6) = cosab</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ELSE IF ( ibrav ==-12 ) THEN</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ! ... monoclinic P lattice, unique axis b</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> celldm(5) = cosac</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ELSE</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ! ... trigonal and monoclinic lattices, unique axis c</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> celldm(4) = cosab</span></p><p class=MsoNormal><span lang=EN-US> !</span></p><p class=MsoNormal><span lang=EN-US> ENDIF</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Then, users have to set gamma (cosab) in an input-file, not alpha (cosbc) or beta (cosac).</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Regards,</span></p><p class=MsoNormal><span lang=EN-US>Satomichi</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:12.0pt;font-family:"ＭＳ Ｐゴシック",sans-serif'><o:p> </o:p></span></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0mm 0mm 0mm'><p class=MsoNormal style='border:none;padding:0mm'><b>差出人<span lang=EN-US>: </span></b><span lang=EN-US><a href="mailto:paolo.giannozzi@uniud.it">Paolo Giannozzi</a><br></span><b>送信日時<span lang=EN-US>: </span></b><span lang=EN-US>2017</span>年<span lang=EN-US>5</span>月<span lang=EN-US>2</span>日<span lang=EN-US> 23:52<br></span><b>宛先<span lang=EN-US>: </span></b><span lang=EN-US><a href="mailto:q-e-developers@qe-forge.org">General discussion list for Quantum ESPRESSO developers</a><br></span><b>件名<span lang=EN-US>: </span></b><span lang=EN-US>Re: [Q-e-developers] ibrav = 5, in INPUT_PW.def</span></p></div><p class=MsoNormal><span lang=EN-US style='font-size:12.0pt;font-family:"ＭＳ Ｐゴシック",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Hi</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>ibrav=5 is the rhombohedral (or trigonal) lattice, having the three</span></p><p class=MsoNormal><span lang=EN-US>angles alpha=beta=gamma/=90. Is there any rule or tradition according</span></p><p class=MsoNormal><span lang=EN-US>to which such angle should be called gamma instead of alpha?</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Paolo</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>On Mon, May 1, 2017 at 8:25 AM, <nisihara225@gmail.com> wrote:</span></p><p class=MsoNormal><span lang=EN-US>> Dear QE-developers,</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>> INPUT_PW.def says that celldm(4) = cos(alpha) when ibrav = +-5.</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>> However, it may be celldm(4) = cos(gamma) to be correct.</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>> Regards,</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>> Satomichi Nishihara</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>> _______________________________________________</span></p><p class=MsoNormal><span lang=EN-US>> Q-e-developers mailing list</span></p><p class=MsoNormal><span lang=EN-US>> Q-e-developers@qe-forge.org</span></p><p class=MsoNormal><span lang=EN-US>> http://qe-forge.org/mailman/listinfo/q-e-developers</span></p><p class=MsoNormal><span lang=EN-US>><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>-- </span></p><p class=MsoNormal><span lang=EN-US>Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,</span></p><p class=MsoNormal><span lang=EN-US>Univ. Udine, via delle Scienze 208, 33100 Udine, Italy</span></p><p class=MsoNormal><span lang=EN-US>Phone +39-0432-558216, fax +39-0432-558222</span></p><p class=MsoNormal><span lang=EN-US>_______________________________________________</span></p><p class=MsoNormal><span lang=EN-US>Q-e-developers mailing list</span></p><p class=MsoNormal><span lang=EN-US>Q-e-developers@qe-forge.org</span></p><p class=MsoNormal><span lang=EN-US>http://qe-forge.org/mailman/listinfo/q-e-developers</span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>