CCL:G: OPT problem

[Soren Eustis <soreneustis*o*gmail.com>]

 Sent to CCL by: Soren Eustis [soreneustis,+,gmail.com]
 You are having problems with the SCF convergence.  One way to overcome this
 is to use the XQC term for the SCF job.  This requests a quadratically
 convergent routing be used if the normal SCF convergence algorithm fails.
 Usually after one or two optimization cycles, the orbitals are sufficiently
 well defined that the SCF energy will converge normally and the job can
 proceed without the costly XQC procedure.
 Your input line would then be:
 #P B3LYP GenECP opt Nosymm SCF=(xqc,NoIncFock) GFINPUT IOp(6/7=3) GFPRINT
 This should work.  If not, you can try a different guess method (i.e.
 Guess=indo).
 Regards,
 Soren
 On 12/3/09 11:28 AM, "Abhishek DuttaChowdhury
 abhishekdc],[chem.iitb.ac.in"
 <owner-chemistry(!)ccl.net> wrote:
 >
 > Sent to CCL by: "Abhishek  DuttaChowdhury"
 [abhishekdc++chem.iitb.ac.in]
 > Dear All,
 >    Following job is stopped after 1st cycle and at the end of output file
 > following error is given:
 >
 >>>>>>>>>>> Convergence criterion not met.
 >  SCF Done:  E(UB+HF-LYP) =  -1958.29938401     A.U. after  129 cycles
 >              Convg  =    0.9641D-06             -V/T =  2.0034
 >              S**2   =   3.1271
 >  KE= 1.951755250014D+03 PE=-1.443854351336D+04 EE= 5.590860464768D+03
 >  Annihilation of the first spin contaminant:
 >  S**2 before annihilation     3.1271,   after     2.2796
 >  Convergence failure -- run terminated.
 >  Error termination via Lnk1e in /g03/l502.exe at Wed Dec  2 04:36:41 2009.
 >  Job cpu time:  1 days  5 hours 27 minutes 12.3 seconds.
 >  File lengths (MBytes):  RWF=    285 Int=      0 D2E=      0 Chk=     10
 > Scr=      1
 >
 >
 > Following is my input file:
 >
 > %chk=cd_opt.chk
 > %mem=500MB
 > #P B3LYP GenECP opt Nosymm SCF=NoIncFock GFINPUT IOp(6/7=3) GFPRINT
 >
 > cd_opt
 >
 > 1 3
 > coordinates
 >
 > C H N O 0
 > 6-31G*
 > ****
 > Si 0
 > LANL2DZ
 > ****
 >
 > Si 0
 > LANL2DZ
 >
 >
 >
 >
 > .............Please give me an indication again that what to do?
 >
 > Many thanks in advance.
 >
 > Sincerely,
 > Abhishek>
 >