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lammps/doc/html/fix_move.html
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<title>fix move command &mdash; LAMMPS documentation</title>
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<div class="lammps_version">Version: <b>19 Nov 2024</b></div>
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<p class="caption" role="heading"><span class="caption-text">User Guide</span></p>
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<li class="toctree-l1"><a class="reference internal" href="Intro.html">1. Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="Install.html">2. Install LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Build.html">3. Build LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Run_head.html">4. Run LAMMPS</a></li>
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<p class="caption" role="heading"><span class="caption-text">Programmer Guide</span></p>
<ul>
<li class="toctree-l1"><a class="reference internal" href="Library.html">1. LAMMPS Library Interfaces</a></li>
<li class="toctree-l1"><a class="reference internal" href="Python_head.html">2. Use Python with LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Modify.html">3. Modifying &amp; extending LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Developer.html">4. Information for Developers</a></li>
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<p class="caption" role="heading"><span class="caption-text">Command Reference</span></p>
<ul class="current">
<li class="toctree-l1"><a class="reference internal" href="commands_list.html">Commands</a></li>
<li class="toctree-l1 current"><a class="reference internal" href="fixes.html">Fix Styles</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="fix_accelerate_cos.html">fix accelerate/cos command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_acks2_reaxff.html">fix acks2/reaxff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_adapt.html">fix adapt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_adapt_fep.html">fix adapt/fep command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_add_heat.html">fix add/heat command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_addforce.html">fix addforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_addtorque.html">fix addtorque command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_alchemy.html">fix alchemy command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_amoeba_bitorsion.html">fix amoeba/bitorsion command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_amoeba_pitorsion.html">fix amoeba/pitorsion command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_append_atoms.html">fix append/atoms command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_atc.html">fix atc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_atom_swap.html">fix atom/swap command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_atom.html">fix ave/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_chunk.html">fix ave/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_correlate.html">fix ave/correlate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_correlate_long.html">fix ave/correlate/long command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_grid.html">fix ave/grid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_histo.html">fix ave/histo command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_histo.html#fix-ave-histo-weight-command">fix ave/histo/weight command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_spatial.html">fix ave/spatial command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_spatial_sphere.html">fix ave/spatial/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ave_time.html">fix ave/time command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_aveforce.html">fix aveforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_balance.html">fix balance command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bocs.html">fix bocs command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bond_break.html">fix bond/break command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bond_create.html">fix bond/create command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bond_create.html#fix-bond-create-angle-command">fix bond/create/angle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bond_react.html">fix bond/react command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_bond_swap.html">fix bond/swap command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_box_relax.html">fix box/relax command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html">fix brownian command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html#fix-brownian-sphere-command">fix brownian/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_brownian.html#fix-brownian-asphere-command">fix brownian/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_charge_regulation.html">fix charge/regulation command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_cmap.html">fix cmap command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_colvars.html">fix colvars command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_controller.html">fix controller command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_damping_cundall.html">fix damping/cundall command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_deform.html">fix deform command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_deform_pressure.html">fix deform/pressure command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_deposit.html">fix deposit command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_dpd_energy.html">fix dpd/energy command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_dpd_source.html">fix edpd/source command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_dpd_source.html#fix-tdpd-source-command">fix tdpd/source command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_drag.html">fix drag command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_drude.html">fix drude command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_drude_transform.html">fix drude/transform/direct command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_drude_transform.html#fix-drude-transform-inverse-command">fix drude/transform/inverse command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_dt_reset.html">fix dt/reset command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_efield.html">fix efield command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_efield.html#fix-efield-tip4p-command">fix efield/tip4p command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ehex.html">fix ehex command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html">fix electrode/conp command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html#fix-electrode-conq-command">fix electrode/conq command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_electrode.html#fix-electrode-thermo-command">fix electrode/thermo command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_electron_stopping.html">fix electron/stopping command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_electron_stopping.html#fix-electron-stopping-fit-command">fix electron/stopping/fit command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_enforce2d.html">fix enforce2d command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_eos_cv.html">fix eos/cv command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_eos_table.html">fix eos/table command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_eos_table_rx.html">fix eos/table/rx command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_evaporate.html">fix evaporate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_external.html">fix external command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ffl.html">fix ffl command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_filter_corotate.html">fix filter/corotate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_flow_gauss.html">fix flow/gauss command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_freeze.html">fix freeze command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_gcmc.html">fix gcmc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_gld.html">fix gld command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_gle.html">fix gle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_gravity.html">fix gravity command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_grem.html">fix grem command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_halt.html">fix halt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_heat.html">fix heat command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_heat_flow.html">fix heat/flow command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_hyper_global.html">fix hyper/global command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_hyper_local.html">fix hyper/local command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_imd.html">fix imd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_indent.html">fix indent command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ipi.html">fix ipi command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_langevin.html">fix langevin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_langevin_drude.html">fix langevin/drude command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_langevin_eff.html">fix langevin/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_langevin_spin.html">fix langevin/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_lb_fluid.html">fix lb/fluid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_lb_momentum.html">fix lb/momentum command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_lb_viscous.html">fix lb/viscous command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_lineforce.html">fix lineforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_manifoldforce.html">fix manifoldforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mdi_qm.html">fix mdi/qm command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mdi_qmmm.html">fix mdi/qmmm command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_meso_move.html">fix meso/move command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mol_swap.html">fix mol/swap command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_momentum.html">fix momentum command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_momentum.html#fix-momentum-chunk-command">fix momentum/chunk command</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">fix move command</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#syntax">Syntax</a></li>
<li class="toctree-l3"><a class="reference internal" href="#examples">Examples</a></li>
<li class="toctree-l3"><a class="reference internal" href="#description">Description</a></li>
<li class="toctree-l3"><a class="reference internal" href="#restart-fix-modify-output-run-start-stop-minimize-info">Restart, fix_modify, output, run start/stop, minimize info</a></li>
<li class="toctree-l3"><a class="reference internal" href="#restrictions">Restrictions</a></li>
<li class="toctree-l3"><a class="reference internal" href="#related-commands">Related commands</a></li>
<li class="toctree-l3"><a class="reference internal" href="#default">Default</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="fix_msst.html">fix msst command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html">fix mvv/dpd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html#fix-mvv-edpd-command">fix mvv/edpd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_mvv_dpd.html#fix-mvv-tdpd-command">fix mvv/tdpd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_neb.html">fix neb command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_neb_spin.html">fix neb/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh.html">fix nvt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh.html#fix-npt-command">fix npt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh.html#fix-nph-command">fix nph command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html">fix nvt/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html#fix-npt-eff-command">fix npt/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh_eff.html#fix-nph-eff-command">fix nph/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh_uef.html">fix nvt/uef command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nh_uef.html#fix-npt-uef-command">fix npt/uef command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nonaffine_displacement.html">fix nonaffine/displacement command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nph_asphere.html">fix nph/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nph_body.html">fix nph/body command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nph_sphere.html">fix nph/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nphug.html">fix nphug command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_npt_asphere.html">fix npt/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_npt_body.html">fix npt/body command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_npt_cauchy.html">fix npt/cauchy command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_npt_sphere.html">fix npt/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_numdiff.html">fix numdiff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_numdiff_virial.html">fix numdiff/virial command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve.html">fix nve command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_asphere.html">fix nve/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_asphere_noforce.html">fix nve/asphere/noforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_awpmd.html">fix nve/awpmd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_body.html">fix nve/body command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_bpm_sphere.html">fix nve/bpm/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_dot.html">fix nve/dot command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_dotc_langevin.html">fix nve/dotc/langevin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_eff.html">fix nve/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_limit.html">fix nve/limit command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_line.html">fix nve/line command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_manifold_rattle.html">fix nve/manifold/rattle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_noforce.html">fix nve/noforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_sphere.html">fix nve/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_spin.html">fix nve/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nve_tri.html">fix nve/tri command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvk.html">fix nvk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_asphere.html">fix nvt/asphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_body.html">fix nvt/body command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_manifold_rattle.html">fix nvt/manifold/rattle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sllod.html">fix nvt/sllod command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sllod_eff.html">fix nvt/sllod/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_nvt_sphere.html">fix nvt/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_oneway.html">fix oneway command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_orient.html">fix orient/fcc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_orient.html#fix-orient-bcc-command">fix orient/bcc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_orient_eco.html">fix orient/eco command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pafi.html">fix pafi command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pair.html">fix pair command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_phonon.html">fix phonon command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pimd.html">fix pimd/langevin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pimd.html#fix-pimd-nvt-command">fix pimd/nvt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pimdb.html">fix pimdb/langevin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pimdb.html#fix-pimdb-nvt-command">fix pimdb/nvt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_planeforce.html">fix planeforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_plumed.html">fix plumed command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_poems.html">fix poems command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html">fix polarize/bem/gmres command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html#fix-polarize-bem-icc-command">fix polarize/bem/icc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_polarize.html#fix-polarize-functional-command">fix polarize/functional command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_pour.html">fix pour command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_precession_spin.html">fix precession/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_press_berendsen.html">fix press/berendsen command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_press_langevin.html">fix press/langevin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_print.html">fix print command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_propel_self.html">fix propel/self command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_property_atom.html">fix property/atom command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_python_invoke.html">fix python/invoke command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_python_move.html">fix python/move command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qbmsst.html">fix qbmsst command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html">fix qeq/point command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-shielded-command">fix qeq/shielded command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-slater-command">fix qeq/slater command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-ctip-command">fix qeq/ctip command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-dynamic-command">fix qeq/dynamic command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq.html#fix-qeq-fire-command">fix qeq/fire command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq_comb.html">fix qeq/comb command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qeq_reaxff.html">fix qeq/reaxff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qmmm.html">fix qmmm command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qtb.html">fix qtb command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_qtpie_reaxff.html">fix qtpie/reaxff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_reaxff_bonds.html">fix reaxff/bonds command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_reaxff_species.html">fix reaxff/species command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_recenter.html">fix recenter command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_restrain.html">fix restrain command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rheo.html">fix rheo command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_oxidation.html">fix rheo/oxidation command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_pressure.html">fix rheo/pressure command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_thermal.html">fix rheo/thermal command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rheo_viscosity.html">fix rheo/viscosity command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rhok.html">fix rhok command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html">fix rigid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nve-command">fix rigid/nve command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nvt-command">fix rigid/nvt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-npt-command">fix rigid/npt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nph-command">fix rigid/nph command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-small-command">fix rigid/small command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nve-small-command">fix rigid/nve/small command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nvt-small-command">fix rigid/nvt/small command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_rigid.html#fix-rigid-nph-small-command">fix rigid/nph/small command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rigid_meso.html">fix rigid/meso command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_rx.html">fix rx command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_saed_vtk.html">fix saed/vtk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_setforce.html">fix setforce command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_setforce.html#fix-setforce-spin-command">fix setforce/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_sgcmc.html">fix sgcmc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_shake.html">fix shake command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_shake.html#fix-rattle-command">fix rattle command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_shardlow.html">fix shardlow command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd.html">fix smd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_adjust_dt.html">fix smd/adjust_dt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_integrate_tlsph.html">fix smd/integrate_tlsph command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_integrate_ulsph.html">fix smd/integrate_ulsph command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_move_triangulated_surface.html">fix smd/move_tri_surf command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_setvel.html">fix smd/setvel command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_smd_wall_surface.html">fix smd/wall_surface command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_sph.html">fix sph command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_sph_stationary.html">fix sph/stationary command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_spring.html">fix spring command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_spring_chunk.html">fix spring/chunk command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_spring_rg.html">fix spring/rg command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_spring_self.html">fix spring/self command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_srd.html">fix srd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_store_force.html">fix store/force command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_store_state.html">fix store/state command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_temp_berendsen.html">fix temp/berendsen command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_temp_csvr.html">fix temp/csvr command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_temp_csvr.html#fix-temp-csld-command">fix temp/csld command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_temp_rescale.html">fix temp/rescale command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_temp_rescale_eff.html">fix temp/rescale/eff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_tfmc.html">fix tfmc command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_tgnh_drude.html">fix tgnvt/drude command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_tgnh_drude.html#fix-tgnpt-drude-command">fix tgnpt/drude command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_thermal_conductivity.html">fix thermal/conductivity command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ti_spring.html">fix ti/spring command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_tmd.html">fix tmd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html">fix ttm command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html#fix-ttm-grid-command">fix ttm/grid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_ttm.html#fix-ttm-mod-command">fix ttm/mod command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_tune_kspace.html">fix tune/kspace command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_vector.html">fix vector command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_viscosity.html">fix viscosity command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_viscous.html">fix viscous command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_viscous_sphere.html">fix viscous/sphere command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html">fix wall/lj93 command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lj126-command">fix wall/lj126 command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lj1043-command">fix wall/lj1043 command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-colloid-command">fix wall/colloid command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-harmonic-command">fix wall/harmonic command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-lepton-command">fix wall/lepton command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall.html#fix-wall-morse-command">fix wall/morse command</a></li>
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<li class="toctree-l2"><a class="reference internal" href="fix_wall_body_polygon.html">fix wall/body/polygon command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_body_polyhedron.html">fix wall/body/polyhedron command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_ees.html">fix wall/ees command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_ees.html#fix-wall-region-ees-command">fix wall/region/ees command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_flow.html">fix wall/flow command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_gran.html">fix wall/gran command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_gran_region.html">fix wall/gran/region command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_piston.html">fix wall/piston command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_reflect.html">fix wall/reflect command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_reflect_stochastic.html">fix wall/reflect/stochastic command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_region.html">fix wall/region command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_wall_srd.html">fix wall/srd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_widom.html">fix widom command</a></li>
</ul>
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<li class="toctree-l1"><a class="reference internal" href="computes.html">Compute Styles</a></li>
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<p><span class="math notranslate nohighlight">\(\renewcommand{\AA}{\text{Å}}\)</span></p>
<section id="fix-move-command">
<span id="index-0"></span><h1>fix move command<a class="headerlink" href="#fix-move-command" title="Link to this heading"></a></h1>
<section id="syntax">
<h2>Syntax<a class="headerlink" href="#syntax" title="Link to this heading"></a></h2>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">fix </span><span class="nv nv-Identifier">ID</span><span class="w"> </span><span class="nv nv-Identifier">group-ID</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="n">style</span><span class="w"> </span><span class="n">args</span><span class="w"> </span><span class="n">keyword</span><span class="w"> </span><span class="n">values</span><span class="w"> </span><span class="n">...</span>
</pre></div>
</div>
<ul>
<li><p>ID, group-ID are documented in <a class="reference internal" href="fix.html"><span class="doc">fix</span></a> command</p></li>
<li><p>move = style name of this fix command</p></li>
<li><p>style = <em>linear</em> or <em>wiggle</em> or <em>rotate</em> or <em>transrot</em> or <em>variable</em></p>
<pre class="literal-block"><em>linear</em> args = Vx Vy Vz
Vx,Vy,Vz = components of velocity vector (velocity units), any component can be specified as NULL
<em>wiggle</em> args = Ax Ay Az period
Ax,Ay,Az = components of amplitude vector (distance units), any component can be specified as NULL
period = period of oscillation (time units)
<em>rotate</em> args = Px Py Pz Rx Ry Rz period
Px,Py,Pz = origin point of axis of rotation (distance units)
Rx,Ry,Rz = axis of rotation vector
period = period of rotation (time units)
<em>transrot</em> args = Vx Vy Vz Px Py Pz Rx Ry Rz period
Vx,Vy,Vz = components of velocity vector (velocity units)
Px,Py,Pz = origin point of axis of rotation (distance units)
Rx,Ry,Rz = axis of rotation vector
period = period of rotation (time units)
<em>variable</em> args = v_dx v_dy v_dz v_vx v_vy v_vz
v_dx,v_dy,v_dz = 3 variable names that calculate x,y,z displacement as function of time, any component can be specified as NULL
v_vx,v_vy,v_vz = 3 variable names that calculate x,y,z velocity as function of time, any component can be specified as NULL</pre>
</li>
<li><p>zero or more keyword/value pairs may be appended</p></li>
<li><p>keyword = <em>units</em></p>
<pre class="literal-block"><em>units</em> value = <em>box</em> or <em>lattice</em></pre>
</li>
</ul>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="n">wiggle</span><span class="w"> </span><span class="m">3.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">1.0</span><span class="w"> </span><span class="n">units</span><span class="w"> </span><span class="n">box</span>
<span class="k">fix </span><span class="nv nv-Identifier">2</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="n">rotate</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">1.0</span><span class="w"> </span><span class="m">5.0</span>
<span class="k">fix </span><span class="nv nv-Identifier">2</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="k">variable </span><span class="nv nv-Identifier">v_myx</span><span class="w"> </span><span class="n">v_myy</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">v_VX</span><span class="w"> </span><span class="n">v_VY</span><span class="w"> </span><span class="n">NULL</span>
<span class="k">fix </span><span class="nv nv-Identifier">3</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="n">transrot</span><span class="w"> </span><span class="m">0.1</span><span class="w"> </span><span class="m">0.1</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">0.0</span><span class="w"> </span><span class="m">1.0</span><span class="w"> </span><span class="m">5.0</span><span class="w"> </span><span class="n">units</span><span class="w"> </span><span class="n">box</span>
</pre></div>
</div>
</section>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
<p>Perform updates of position and velocity for atoms in the group each
timestep using the specified settings or formulas, without regard to
forces on the atoms. This can be useful for boundary or other atoms,
whose movement can influence nearby atoms.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The atoms affected by this fix should not normally be time integrated
by other fixes (e.g. <a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a>, <a class="reference internal" href="fix_nh.html"><span class="doc">fix nvt</span></a>), since that will change their positions and velocities
twice.</p>
</div>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>As atoms move due to this fix, they will pass through periodic
boundaries and be remapped to the other side of the simulation box,
just as they would during normal time integration (e.g. via the
<a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a> command). It is up to you to decide whether
periodic boundaries are appropriate with the kind of atom motion you
are prescribing with this fix.</p>
</div>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>As discussed below, atoms are moved relative to their initial
position at the time the fix is specified. These initial coordinates
are stored by the fix in “unwrapped” form, by using the image flags
associated with each atom. See the <a class="reference internal" href="dump.html"><span class="doc">dump custom</span></a> command
for a discussion of “unwrapped” coordinates. See the Atoms section
of the <a class="reference internal" href="read_data.html"><span class="doc">read_data</span></a> command for a discussion of image
flags and how they are set for each atom. You can reset the image
flags (e.g. to 0) before invoking this fix by using the <a class="reference internal" href="set.html"><span class="doc">set
image</span></a> command.</p>
</div>
<hr class="docutils" />
<p>The <em>linear</em> style moves atoms at a constant velocity, so that their
position <em>X</em> = (x,y,z) as a function of time is given in vector
notation as</p>
<pre class="literal-block">X(t) = X0 + V * delta</pre>
<p>where <em>X0</em> = (x0,y0,z0) is their position at the time the fix is
specified, <em>V</em> is the specified velocity vector with components
(Vx,Vy,Vz), and <em>delta</em> is the time elapsed since the fix was
specified. This style also sets the velocity of each atom to V =
(Vx,Vy,Vz). If any of the velocity components is specified as NULL,
then the position and velocity of that component is time integrated
the same as the <a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a> command would perform, using
the corresponding force component on the atom.</p>
<p>Note that the <em>linear</em> style is identical to using the <em>variable</em>
style with an <a class="reference internal" href="variable.html"><span class="doc">equal-style variable</span></a> that uses the
vdisplace() function. E.g.</p>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">variable </span><span class="nv nv-Identifier">V</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="m">10.0</span>
<span class="k">variable </span><span class="nv nv-Identifier">x</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="n">vdisplace</span><span class="nv">(0.0,$V)</span>
<span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="k">variable </span><span class="nv nv-Identifier">v_x</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">v_V</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">NULL</span>
</pre></div>
</div>
<p>The <em>wiggle</em> style moves atoms in an oscillatory fashion, so that
their position <em>X</em> = (x,y,z) as a function of time is given in vector
notation as</p>
<pre class="literal-block">X(t) = X0 + A sin(omega*delta)</pre>
<p>where <em>X0</em> = (x0,y0,z0) is their position at the time the fix is
specified, <em>A</em> is the specified amplitude vector with components
(Ax,Ay,Az), <em>omega</em> is 2 PI / <em>period</em>, and <em>delta</em> is the time elapsed
since the fix was specified. This style also sets the velocity of each
atom to the time derivative of this expression. If any of the amplitude
components is specified as NULL, then the position and velocity of that
component is time integrated the same as the <a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a>
command would perform, using the corresponding force component on the
atom.</p>
<p>Note that the <em>wiggle</em> style is identical to using the <em>variable</em>
style with <a class="reference internal" href="variable.html"><span class="doc">equal-style variables</span></a> that use the
swiggle() and cwiggle() functions. E.g.</p>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">variable </span><span class="nv nv-Identifier">A</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="m">10.0</span>
<span class="k">variable </span><span class="nv nv-Identifier">T</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="m">5.0</span>
<span class="k">variable </span><span class="nv nv-Identifier">omega</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="m">2.0</span><span class="o">*</span><span class="n">PI</span><span class="o">/</span><span class="nv">$T</span>
<span class="k">variable </span><span class="nv nv-Identifier">x</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="n">swiggle</span><span class="nv">(0.0,$A,$T)</span>
<span class="k">variable </span><span class="nv nv-Identifier">v</span><span class="w"> </span><span class="n">equal</span><span class="w"> </span><span class="n">v_omega</span><span class="o">*</span><span class="nv">($A-cwiggle(0.0,$A,$T))</span>
<span class="k">fix </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">boundary</span><span class="w"> </span><span class="n">move</span><span class="w"> </span><span class="k">variable </span><span class="nv nv-Identifier">v_x</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">v_v</span><span class="w"> </span><span class="n">NULL</span><span class="w"> </span><span class="n">NULL</span>
</pre></div>
</div>
<p>The <em>rotate</em> style rotates atoms around a rotation axis <em>R</em> = (Rx,Ry,Rz)
that goes through a point <em>P</em> = (Px,Py,Pz). The <em>period</em> of the
rotation is also specified. The direction of rotation for the atoms
around the rotation axis is consistent with the right-hand rule: if your
right-hand thumb points along <em>R</em>, then your fingers wrap around the
axis in the direction of rotation.</p>
<p>This style also sets the velocity of each atom to (omega cross Rperp)
where omega is its angular velocity around the rotation axis and Rperp
is a perpendicular vector from the rotation axis to the atom. If the
defined <a class="reference internal" href="atom_style.html"><span class="doc">atom_style</span></a> assigns an angular velocity or
angular momentum or orientation to each atom (<a class="reference internal" href="atom_style.html"><span class="doc">atom styles</span></a> sphere, ellipsoid, line, tri, body), then
those properties are also updated appropriately to correspond to the
atoms motion and rotation over time.</p>
<p>The <em>transrot</em> style combines the effects of <em>rotate</em> and <em>linear</em> so
that it is possible to prescribe a rotating group of atoms that also
moves at a constant velocity. The arguments are for the translation
first and then for the rotation. Since the rotation affects all
coordinate components, it is not possible to set any of the
translation vector components to NULL.</p>
<p>The <em>variable</em> style allows the position and velocity components of
each atom to be set by formulas specified via the
<a class="reference internal" href="variable.html"><span class="doc">variable</span></a> command. Each of the 6 variables is
specified as an argument to the fix as v_name, where name is the
variable name that is defined elsewhere in the input script.</p>
<p>Each variable must be of either the <em>equal</em> or <em>atom</em> style.
<em>Equal</em>-style variables compute a single numeric quantity, that can be
a function of the timestep as well as of other simulation values.
<em>Atom</em>-style variables compute a numeric quantity for each atom, that
can be a function per-atom quantities, such as the atoms position, as
well as of the timestep and other simulation values. Note that this fix
stores the original coordinates of each atom (see note below) so that
per-atom quantity can be used in an atom-style variable formula. See
the <a class="reference internal" href="variable.html"><span class="doc">variable</span></a> command for details.</p>
<p>The first 3 variables (v_dx,v_dy,v_dz) specified for the <em>variable</em>
style are used to calculate a displacement from the atoms original
position at the time the fix was specified. The second 3 variables
(v_vx,v_vy,v_vz) specified are used to compute a velocity for each
atom.</p>
<p>Any of the 6 variables can be specified as NULL. If both the
displacement and velocity variables for a particular x,y,z component
are specified as NULL, then the position and velocity of that
component is time integrated the same as the <a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a>
command would perform, using the corresponding force component on the
atom. If only the velocity variable for a component is specified as
NULL, then the displacement variable will be used to set the position
of the atom, and its velocity component will not be changed. If only
the displacement variable for a component is specified as NULL, then
the velocity variable will be used to set the velocity of the atom,
and the position of the atom will be time integrated using that
velocity.</p>
<p>The <em>units</em> keyword determines the meaning of the distance units used
to define the <em>linear</em> velocity and <em>wiggle</em> amplitude and <em>rotate</em>
origin. This setting is ignored for the <em>variable</em> style. A <em>box</em>
value selects standard units as defined by the <a class="reference internal" href="units.html"><span class="doc">units</span></a>
command, e.g. velocity in Angstroms/fs and amplitude and position
in Angstroms for units = real. A <em>lattice</em> value means the velocity
units are in lattice spacings per time and the amplitude and position
are in lattice spacings. The <a class="reference internal" href="lattice.html"><span class="doc">lattice</span></a> command must have
been previously used to define the lattice spacing. Each of these 3
quantities may be dependent on the x,y,z dimension, since the lattice
spacings can be different in x,y,z.</p>
</section>
<hr class="docutils" />
<section id="restart-fix-modify-output-run-start-stop-minimize-info">
<h2>Restart, fix_modify, output, run start/stop, minimize info<a class="headerlink" href="#restart-fix-modify-output-run-start-stop-minimize-info" title="Link to this heading"></a></h2>
<p>This fix writes the original coordinates of moving atoms to <a class="reference internal" href="restart.html"><span class="doc">binary
restart files</span></a>, as well as the initial timestep, so that the
motion can be continuous in a restarted simulation. See the
<a class="reference internal" href="read_restart.html"><span class="doc">read_restart</span></a> command for info on how to re-specify
a fix in an input script that reads a restart file, so that the
operation of the fix continues in an uninterrupted fashion.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>Because the move positions are a function of the current
timestep and the initial timestep, you cannot reset the timestep to a
different value after reading a restart file, if you expect a fix move
command to work in an uninterrupted fashion.</p>
</div>
<p>None of the <a class="reference internal" href="fix_modify.html"><span class="doc">fix_modify</span></a> options are relevant to this
fix.</p>
<p>This fix produces a per-atom array which can be accessed by various
<a class="reference internal" href="Howto_output.html"><span class="doc">output commands</span></a>. The number of columns for each
atom is 3, and the columns store the original unwrapped x,y,z coords of
each atom. The per-atom values can be accessed on any timestep.</p>
<p>No parameter of this fix can be used with the <em>start/stop</em> keywords of
the <a class="reference internal" href="run.html"><span class="doc">run</span></a> command. This fix is not invoked during
<a class="reference internal" href="minimize.html"><span class="doc">energy minimization</span></a>.</p>
<p>For <a class="reference internal" href="run_style.html"><span class="doc">rRESPA time integration</span></a>, this fix adjusts the
position and velocity of atoms on the outermost rRESPA level.</p>
</section>
<section id="restrictions">
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Link to this heading"></a></h2>
<blockquote>
<div><p>none</p>
</div></blockquote>
</section>
<section id="related-commands">
<h2>Related commands<a class="headerlink" href="#related-commands" title="Link to this heading"></a></h2>
<p><a class="reference internal" href="fix_nve.html"><span class="doc">fix nve</span></a>, <a class="reference internal" href="displace_atoms.html"><span class="doc">displace_atoms</span></a></p>
</section>
<section id="default">
<h2>Default<a class="headerlink" href="#default" title="Link to this heading"></a></h2>
<p>none</p>
<p>The option default is units = lattice.</p>
</section>
</section>
</div>
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