Re: AMBER: Problem with divcon - increasing MXATTS?

From: Kennie Merz <merz.psu.edu>
Date: Wed, 14 Jul 2004 12:01:54 -0400

Hi,
  Try OPT=LBFGS rather than OPT=BFGS. That should eliminate the problem.
Kennie


On Jul 14, 2004, at 11:33 AM, steven.j.enoch.gsk.com wrote:

>
> Amber users,
>
> I am trying use antechamber to create prep (and frcmod) files for a
> large ligand (126 atoms).  It is essentially two protien chains linked
> together by an organic backbone.  When I run antechamber I get the
> following error message:
>
> CARTESIAN AM1 STANDARD DIRECT OPT=BFGS XTEST=0.0001 CHARGE=-3        
>          
>
> created by wmopcrt()                                                  
>          
>
>
>  CARTESIAN      - CARTESIAN COORDINATE FORMAT SELECTED
>  AM1            - AM1 HAMILTONIAN TO BE USED
>  STANDARD       - STANDARD CLOSED-SHELL CALCULATION (NO D&C)
>  DIRECT         - DO NOT STORE 2-ELECTRON INTEGRALS IN SCF CALCULATIONS
>  OPT=BFGS       - CARRY OUT A BFGS GEOMETRY OPTIMIZATION
>  XTEST=0.0001   - GEOMETRY OPTIMIZATION COORDINATE CHANGE CRITERION =
> 0.00010
>  CHARGE=-3      - A NET CHARGE OF    -3.00 TO BE PLACED ON SYSTEM
>
>
>  NUMBER OF ATOMS                 =   124
>  TOTAL NUMBER OF BASIS FUNCTIONS =   313
>  TOTAL NUMBER OF ELECTRONS       =   352
>
>
>  DEFAULT SETTINGS FOR CALCULATION
>  --------------------------------
>
>  - D&C TEMPERATURE OF 1000.00 K WILL BE USED
>  - NO TIME LIMIT ON CALCULATION
>  
>
>  ETEST  =  0.002000
>  XTEST  =  0.000100
>  GNTEST =  2.410913
>  GTEST  =  0.500000
>
>  NUMBER OF VARIABLES=   372
>
>  UPDATING PAIRLIST
>  NPAIRS =     7626
>
>   CYCLE =     0         TIME =     47.565  ENERGY =    -405.624288
>   GNORM =    473.513  GRDMAX =  114.8450   GRDAVR =   17.6764
>  DELTAE =    0.000000 DELTAX = 0.000000
>
>   MAXIMUM NUMBER OF ATOMS IN BFGS SEARCH EXCEDEED
>
>   Max Degree =   180 NPAR=   372
>
>   INCREASE MXATTS IN divcon.dim AND RECOMPILE
>
>
>  FINAL QUANTITIES:
>  -----------------
>
>  NUMBER OF FULLY DIAGONALIZED SUBSYSTEMS:      1
>  NUMBER OF FROZEN SUBSYSTEMS:                  0
>  NUMBER OF SCF CALCULATIONS =      1
>
>  ELECTRONIC ENERGY     =          -143107.91168290 EV
>  CORE-CORE REPULSIONS  =           130880.02283529 EV
>  TOTAL ENERGY          =           -12227.88884761 EV
>  HEAT OF FORMATION     =             -405.62428815 KCAL/MOL
>  FERMI ENERGY          =                0.00000000 EV
>
>
> I have tried increasing MXATTS to 150 (and then 400) and then
> recompiled divcon, but I still get the same error message.  Does
> anybody have any advice on how to get around this problem? Or can
> divcon not deal with such a large ligand?
>
> Many thanks
>
> Dr Steve Enoch
> GlaxoSmithKline
> UK
Professor Kenneth M. Merz, Jr.
152 Davey Laboratory
Department of Chemistry
The Pennsylvania State University
University Park, Pennsylvania 16802

e-mail: merz.psu.edu
http: http://merz.chem.psu.edu
QBio DB: http://qbiodb.chem.psu.edu

Phone: 814-865-3623
FAX: 814-863-8403
Cell: 814-360-0376


-----------------------------------------------------------------------
The AMBER Mail Reflector
To post, send mail to amber.scripps.edu
To unsubscribe, send "unsubscribe amber" to majordomo.scripps.edu
Received on Wed Jul 14 2004 - 17:53:01 PDT
Custom Search