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<DIV><FONT face=Verdana size=2>dear molpro-user</FONT></DIV>
<DIV> </DIV>
<DIV>I was puzzled by irc problem recently. The following example is
given in the molpro manual (version 2010)</DIV>
<DIV> </DIV>
<DIV>
<DIV>!examples/hcn_isomerization.com $Revision: 2010.1 $</DIV>
<DIV> ***, HCN <---> NHC Isomerization Reaction Path</DIV>
<DIV> memory,1,m</DIV>
<DIV> basis=3-21G</DIV>
<DIV></DIV>
<DIV> rcn=1.18282 ang ! Starting geometry is transition state</DIV>
<DIV> rnh=1.40745 ang</DIV>
<DIV> alpha=55.05 degree</DIV>
<DIV></DIV>
<DIV> symmetry,x ! Cs Symmetry</DIV>
<DIV> geometry={</DIV>
<DIV> C</DIV>
<DIV> N,1,rcn</DIV>
<DIV> H,2,rnh,1,alpha}</DIV>
<DIV></DIV>
<DIV> int</DIV>
<DIV> rhf</DIV>
<DIV> optg,root=2,saveact=hcn_ts,rewind ! Find and store the TS</DIV>
<DIV> {optg,method=qsdpath,dir=1, numhess=5,hesscentral,saveact=hcn_path} ! find IRC in positive direction</DIV>
<DIV></DIV>
<DIV> readvar,hcn_ts.act ! Reset geometry to TS</DIV>
<DIV> {optg,method=qsdpath,dir=-1,numhess=5,hesscentral,saveact=hcn_path,append} !find IRC in negative direction</DIV>
<DIV></DIV>
<DIV> readvar,hcn_path.act</DIV>
<DIV></DIV>
<DIV> alpha=alpha*pi/180 !convert angle to radian</DIV>
<DIV></DIV>
<DIV> table,irc,rcn,rnh,alpha,e_opt !tabulate results</DIV>
<DIV></DIV>
<DIV> {table,irc,e_opt !plot energy profile as function of irc</DIV>
<DIV> plot,file='hcn_eopt.plot'}</DIV>
<DIV></DIV>
<DIV> {table,irc,rcn,rnh,alpha !plot distances and angle as function of irc</DIV>
<DIV> plot,file='hcn_dist.plot'}</DIV></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV> </DIV>
<DIV>The output should leads to product HCN and HNC whereas in
fact it is not. similarly, for my own molecules I also didn't get the
desired result. </DIV>
<DIV> </DIV>
<DIV>what's wrong with the input?</DIV>
<DIV> </DIV>
<DIV align=left><FONT face=Verdana color=#c0c0c0 size=2>2011-05-31
</FONT></DIV><FONT face=Verdana size=2>
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<DIV><FONT face=Verdana color=#c0c0c0 size=2><SPAN>gaosm09</SPAN>
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