<div dir="ltr"><br><br>On Saturday, March 11, 2017 at 1:02:25 PM UTC-5, Marcella Iannuzzi wrote:<blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;"><div dir="ltr">Hi<div><br></div><div>In addition to the original papers, where these parameters are discussed, </div><div>there are several review papers on metadynamics, and many applications of the method in different field, where these topics are  also discussed.</div><div>For example </div><div><a onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fpubs.acs.org%2Fdoi%2Fabs%2F10.1021%2Fjp045424k\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNEZgBLIY6bocMLFIXYEr9X0EfnVEw';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fpubs.acs.org%2Fdoi%2Fabs%2F10.1021%2Fjp045424k\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNEZgBLIY6bocMLFIXYEr9X0EfnVEw';return true;" href="http://pubs.acs.org/doi/abs/10.1021/jp045424k" target="_blank" rel="nofollow">http://pubs.acs.org/doi/abs/<wbr>10.1021/jp045424k</a><br></div><div><a onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fwcms.31%2Ffull\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGxUrSym-8hvokyAKRb2KS4UCCNDg';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fonlinelibrary.wiley.com%2Fdoi%2F10.1002%2Fwcms.31%2Ffull\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGxUrSym-8hvokyAKRb2KS4UCCNDg';return true;" href="http://onlinelibrary.wiley.com/doi/10.1002/wcms.31/full" target="_blank" rel="nofollow">http://onlinelibrary.wiley.<wbr>com/doi/10.1002/wcms.31/full</a><br></div><div><a onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fiopscience.iop.org%2Farticle%2F10.1088%2F0034-4885%2F71%2F12%2F126601%2Fmeta\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGpS5Fm6PZLLgs2-9s9QNwGD8IOKw';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fiopscience.iop.org%2Farticle%2F10.1088%2F0034-4885%2F71%2F12%2F126601%2Fmeta\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNGpS5Fm6PZLLgs2-9s9QNwGD8IOKw';return true;" href="http://iopscience.iop.org/article/10.1088/0034-4885/71/12/126601/meta" target="_blank" rel="nofollow">http://iopscience.iop.org/<wbr>article/10.1088/0034-4885/71/<wbr>12/126601/meta</a></div><div>Obviously these choices and parameters are strongly system dependent.</div><div>This is not a cp2k specific  question. </div><div>Anyway, I guess you mean Lagrangian method for metadynamics, and not Langevin. Though metadynamics has been combined also with the Langevin equation:</div><div><a onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fjournals.aps.org%2Fprl%2Fabstract%2F10.1103%2FPhysRevLett.96.090601\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNFNwW_nyinWiLgkPhynzHpTRQn7SA';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fjournals.aps.org%2Fprl%2Fabstract%2F10.1103%2FPhysRevLett.96.090601\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNFNwW_nyinWiLgkPhynzHpTRQn7SA';return true;" href="http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.96.090601" target="_blank" rel="nofollow">http://journals.aps.org/prl/<wbr>abstract/10.1103/PhysRevLett.<wbr>96.090601</a><br></div><div><br></div><div>kind regards</div><div>Marcella</div><div><br></div><div><br><br>On Saturday, March 11, 2017 at 4:09:05 PM UTC+1, Anthony Debellis wrote:<blockquote class="gmail_quote" style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;"><div dir="ltr"><div>I am a new cp2k user who would like to run some metadynamics (DFT) simulations.  I have defined a collective variable of the bond length difference for 3 atoms.  After running unbiased dynamics for 15ps I can see that the CV fluctuates between 3-5 bohr.  I would like some advice on setting the parameters for a biased metadynamics run.  For example, what are reasonable values for the hill height (I expect the barrier of the relevant process to be ~35kj/mol), the hill width, the # of steps between hill growth, the langevin parameters of spring constant and particle mass?  What is the benefit of running the langevin method versus direct metadynamics?  I would greatly appreciate any help offered.  Please include keywords and units!</div><div><br></div><div>Regards,</div><div>Anthony</div></div></blockquote></div></div></blockquote><div><br></div><div><br></div><div>Many thanks for the quick reply.  The references will be very useful.  Yes, I am referring to the lagrangian method (sorry for the mistype!).</div><div><br></div><div>Regards,</div><div>Anthony</div><div> </div></div>