https://vasp.at/wiki/index.php?action=history&feed=atom&title=LPHON_READ_FORCE_CONSTANTS 2026-04-15T18:51:57Z Revision history for this page on the wiki MediaWiki 1.43.8 https://vasp.at/wiki/index.php?title=LPHON_READ_FORCE_CONSTANTS&diff=18945&oldid=prev 2022-09-01T09:49:45Z

<p>Created page with &quot;{{DISPLAYTITLE:LPHON_READ_FORCE_CONSTANTS}} {{TAGDEF|LPHON_READ_FORCE_CONSTANTS|.TRUE. {{!}} .FALSE. }} {{DEF|LPHON_READ_FORCE_CONSTANTS|.FALSE.|}} Description: {{TAG|LPHON_R...&quot;</p> <p><b>New page</b></p><div>{{DISPLAYTITLE:LPHON_READ_FORCE_CONSTANTS}}<br /> {{TAGDEF|LPHON_READ_FORCE_CONSTANTS|.TRUE. {{!}} .FALSE. }}<br /> {{DEF|LPHON_READ_FORCE_CONSTANTS|.FALSE.|}}<br /> <br /> Description: {{TAG|LPHON_READ_FORCE_CONSTANTS}} read the force constants from a vaspin.h5 file containing the force constants computed with a previous VASP run.<br /> <br /> ----<br /> <br /> After the computation of the force constants using finite-differences ({{TAG|IBRION}}=5,6) or density-functional perturbation theory ({{TAG|IBRION}}=7,8) on a supercell the force constants are written to the vaspout.h5 file.<br /> To plot the phonon dispersion on a different path the user can modify the {{FILE|QPOINTS}} file and read the force constants computed previously (i.e. without performing the finite-differences computations on supercells again).<br /> To do so copy vaspout.h5 to vaspin.h5 and set {{TAG|LPHON_READ_FORCE_CONSTANTS}}=.TRUE. in the {{FILE|INCAR}} file.<br /> Note that when this is set only the phonon dispersion is performed and then VASP quits without running any additional calculation specified in the {{TAG|INCAR}} file.<br /> {{NB|mind| Only available as of VASP 6.4.0.}}<br /> <br /> ==Related tags and articles==<br /> {{FILE| QPOINTS}},<br /> {{TAG | LPHON_DISPERSION}},<br /> {{TAG | PHON_NWRITE}},<br /> {{TAG | LPHON_POLAR}},<br /> {{TAG | PHON_DIELECTRIC}},<br /> {{TAG | PHON_BORN_CHARGES}},<br /> {{TAG | PHON_G_CUTOFF}}<br /> <br /> {{sc|LPHON_DISPERSION|Examples|Examples that use this tag}}<br /> <br /> [[Category:INCAR tag]][[Category:Phonons]]</div>

Miranda.henrique