CCL:G: SCF convergence problem with M06L functional in Gaussian 09

 Sent to CCL by: "Close, David M." [CLOSED : mail.etsu.edu]
 Bulumoni:
   If the solution is oscillating, then adding more cycles will not help.  It
 would be best to animate the output and see which part of the molecule is
 changing.  Usually this is evident.  Perhaps some rocking motion.  Anyway, find
 the atoms involved and freeze their motion.  Then the optimization will converge
 rapidly.
   Regards, Dave Close.
 -----Original Message-----
 > From: owner-chemistry+closed==etsu.edu . ccl.net [mailto:owner-chemistry+closed==etsu.edu . ccl.net] On Behalf Of Bulumoni
 Kalita bulumoni:dibru.ac.in
 Sent: Friday, February 26, 2016 12:12 AM
 To: Close, David M. <CLOSED . mail.etsu.edu>
 Subject: CCL:G: SCF convergence problem with M06L functional in Gaussian 09
 Sent to CCL by: "Bulumoni  Kalita" [bulumoni- -dibru.ac.in] Dear CCL
 users,
        I have optimized tetrahedral structure of Pd4 cluster in (UB3LYP/LANL2DZ)
 level in Gaussian 09. I wanted to repeat the calculation in (UM06L/LANL2DZ)
 level.  However, SCF is not converging in this case.  Rather it is fluctuating
 between to range of values.  I have tried using SCF(xqc, maxcycle=500),
 opt(maxcycle=500) etc.
 Please give your valuable suggestions to overcome this problem.http://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp-:-//www.ccl.net/chemistry/sub_unsub.shtmlhttp-:-//www.ccl.net/spammers.txt