Talk:Code

From Henkelman Group

A recent change has been made to the OPTIMIZERS in vasp. I have added this new global NEB for use with the LBFGS optimizer. It also works for regular minimazations. I have not tested it with the dimer but my guess is it should also work. If the emprical data I took is any indication this should be on the order of 3x as fast for NEB compaired to QUICKMIN

in the INCAR these are the paramiters you should set

IBRION=3 POTIM=0.0

IOPT=1 OPTGLOBAL=.TRUE. INVCURV=0.01

INVCURV is the knob to set the inital hessain. If it seems to go out of control make that term smaller you can also play with

LBFGSMEM

the default is 20 but higher would not hurt (this is how many steps it remembers) As always let me know about bugs you find

Dan

a note on MAXMOVE set max move how you always would (maxmove per image) The global system with use a MAXMOVE scaled by the number of images

formally it is: maxmove_global= Sqrt( images*maxmove**2 ) if you care