CCL:G: OPTIMIZATION PROBLEM

[Goedele Roos <groos{=}vub.ac.be>]

 Sent to CCL by: Goedele Roos [groos{:}vub.ac.be]
 Hi,
 try opt=tight
 and a larger basis set on the Cl
 Goedele
 >Hi,
 >I have tried with scf=tight, but it didn't work. What is happening is 4 Cl
 atom is going far apart from each other. But its crystal structure shows it
 should be stable structure.Please help.
 >regards.
 >Partha
 >
 >
 >
 >________________________________
 >From: partha kundu <partha1kundu() yahoo.com>
 >To: CCL Subscribers <chemistry() ccl.net>
 >Sent: Friday, 4 November 2011 9:13 AM
 >Subject: Re: CCL:G: OPTIMIZATION PROBLEM
 >
 >
 >Thank you Bradley for your help. I will try and let you know.
 >regards.
 >Partha.
 >
 >
 >________________________________
 >From: Bradley Welch bwelch5]![slu.edu <owner-chemistry() ccl.net>
 >To: "Kundu, Partha Pratim " <partha1kundu() yahoo.com>
 >Sent: Thursday, 3 November 2011 5:57 PM
 >Subject: CCL:G: OPTIMIZATION PROBLEM
 >
 >
 >Have you tried using scf=tight. Usually scf=qc is used when the standard scf
 calculation fails. 
 >
 >
 >Also, have you considered a slightly larger basis set on
 those chlorines? That seems like a very small basis set.
 >
 >
 >Bradley Welch 
 >
 >
 >On Thu, Nov 3, 2011 at 1:39 AM, Partha p kundu partha1kundu|yahoo.com
 <owner-chemistry-x-ccl.net> wrote:
 >
 >
 >>Sent to CCL by: "Partha p kundu" [partha1kundu-*-yahoo.com]
 >>Dear All,
 >>I have some problem in optimizing a geometry. My input file is the
 following.
 >>
 >>
 >>%chk=cd.chk
 >>%mem=200MW
 >>%nproc=4
 >>#opt b3lyp/gen pseudo=read scf=qc nosym
 >>
 >>Title Card Required
 >>
 >> -4 1
 >> Cd              
  -1.05043015   -3.48046330    235727072
 >> Cl                
 0.40206012   -5.72017854    249396286
 >> Cl                
 1.00016821   -2.12566780    292423554
 >> Cl              
  -2.50292042   -1.24074806    222057858
 >> Cl              
  -0.43020500   -3.31734213   -0.23761836
 >> Cl              
  -1.67065530   -3.64358447    495215980
 >> Cl              
  -3.10102851   -4.83525880    179030589
 >>
 >> Cl 0
 >> 3-21G
 >> ****
 >> Cd 0
 >> LANL2DZ
 >> ****
 >>
 >> Cd
 >> LANL2DZ
 >>
 >>Last few lines of my output is saying
 >>
 >>Linear equations converged to 2.037D-10 2.037D-09 after   3
 iterations.
 >> Search did not lower the energy significantly.
 >> No lower point found -- try reversing direction.
 >> Search did not lower the energy significantly.
 >> No lower point found -- switch to scaled steepest descent.
 >> Search did not lower the energy significantly.
 >> Scaled steepest descent with Shift=0.000 failed.
 >> Search did not lower the energy significantly.
 >> Scaled steepest descent with Shift=0.025 failed.
 >> Search did not lower the energy significantly.
 >> Scaled steepest descent with Shift=0.050 failed.
 >> Search did not lower the energy significantly.
 >> Scaled steepest descent with Shift=0.075 failed.
 >> Search did not lower the energy significantly.
 >> No lower point found -- switch to steepest descent.
 >> Search did not lower the energy significantly.
 >> No lower point found -- run aborted.
 >> Error termination via Lnk1e in C:G03Wl508.exe at Thu Nov 03
 11:48:56 2011.
 >>
 >>
 >>Please help. Thanks in advance.
 >>regards.
 >>Partha.>>
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 >>     http://www.ccl.net/cgi-bin/ccl/send_ccl_message
 >>
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 >>
 >>
 >
 _____________________________
 Goedele Roos, PhD
 Department of General Chemistry http://we.vub.ac.be/~algc/
 VIB, Department of Structural Biology, Vrije Universiteit Brussel | http://www.structuralbiology.be/
 Brussels Center for Redox Biology | http://redox.vub.ac.be/
 Vrije Universiteit Brussel, Building G, room 10G714
 Pleinlaan 2, 1050 Brussels,Belgium
 phone: +32 2 6293312
 fax: +32 2 6293317
 E-mail: groos_-_vub.ac.be