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["Josef W. Zwanziger" <jzwanzig@jzwanzig.org>]

Is this structure also CaLi2, as in your earlier post? If so, the input looks 
very hard to understand to me. Why do you have lots of xred entries with 
values like 4.1..., 5.1....? Why are they not all between -1 and 1? Where did 
you get these entries? Have you tried running just an scf calc from the 
crystal structure data?

spgroup 194
acell 6.268 6.268 10.219 angstrom
angdeg 90.0 90.0 120.0
kptopt 1
kptrlen 47
znucl 20 3
ntypat 2
typat 1 2 2
natom 12
natrd 3
xred
1/3 2/3 0.0627 # Calcium at Wyckoff 4f (1/3 2/3 z)
0   0   0      # Lithium at Wyckoff 2a (0 0 0)
0.167 0.334 1/4 # Lithium at Wyckoff 6h (x 2x 1/4)

this lets abinit do all the hard work for you. In your input, I can't 
identify in particular the Li 6h site. Are you starting from a really 
different crystal structure?

Which pseudos are you using? 

 Josef W. Zwanziger
Professor of Chemistry
Canada Research Chair in NMR Studies of Materials
Director, Atlantic Region Magnetic Resonance Centre
Department of Chemistry
Dalhousie University
6274 Coburg Road
Halifax, Nova Scotia B3H 4J3 Canada
tel: +1.902.494.1960
fax: +1.902.494.1310
web: http://jwz.chem.dal.ca
jzwanzig@jzwanzig.org,jzwanzig@dal.ca



----- Original Message ----
> From: 程迎春 <watermall@126.com>
> To: abinit <forum@abinit.org>
> Sent: Tuesday, December 16, 2008 11:54:15 PM
> Subject: {Spam?} [abinit-forum] {Spam?} optimize structure under pressure
> 
> Dear abinit users，
>       I want to optimize the structure under isotropic pressure using the 
> KEY 
> word "strtarget". But there are some error in the log file.  The following 
> is 
> the complaint message:
> ===================================================================================
> BROYDEN STEP NUMBER   2  
> ------------------------------------------------------
> 
> metric : ERROR -
>   Current rprimd gives negative (R1xR2).R3 .
>   Rprimd =   -5.132223E+01    2.963090E+01    0.000000E+00
>               0.000000E+00   -5.926181E+01    0.000000E+00
>               0.000000E+00    0.000000E+00   -9.492747E+01
>   Action : if the cell size and shape are fixed (optcell==0),
>    exchange two of the input rprim vectors;
>    if you are optimizing the cell size and shape (optcell/=0),
>    maybe the move was too large, and you might try to decrease strprecon.
> -P-0000
> -P-0000  leave_new : decision taken to exit ...
> ===================================================================================
> Following the suggestion above, I decrease strprecon to 0.02, but the error 
> remains. My crystal is hexagonal structure.  Any suggestion is appreciated. 
>    
> The following is the input file. Thank you in advance!
> ===================================================================================
> strtarget 0.000679785784544 0.000679785784544 0.000679785784544 0 0 0
> strprecon 0.02 
> ionmov 2
> optcell 2 
> ntime 100
> nline 6
> tolmxf 1.0d-3
> dilatmx 2.5
> ecutsm  0.5
> kptopt   1 
> ngkpt 4 4 4
> nshiftk 1
> shiftk 0.0 0.0 0.5
> iscf   3    
> ntypat 2        
> znucl 3 20
> natom 12  
> typat 1 1 1 1 1 1 1 1 2 2 2 2
> nband  30    
> ixc 1            
> ecut    25          
> occopt 7
> tsmear 0.01 
> nstep 100              
> toldfe 1.0d-7
> # Lattice setup
>      acell    1.1436136526E+01  1.1436136526E+01  1.8454074412E+01 Bohr
>      rprim    8.6602540378E-01 -5.0000000000E-01  0.0000000000E+00
>               0.0000000000E+00  1.0000000000E+00  0.0000000000E+00
>               0.0000000000E+00  0.0000000000E+00  1.0000000000E+00
> 
>       xred    0.0000000000E+00  0.0000000000E+00 -2.0816681712E-16
>               0.0000000000E+00  0.0000000000E+00  5.0000000000E-01
>               5.1671769153E+00  9.3343538307E+00  2.5000000000E-01
>              -9.3343538307E+00 -4.1671769153E+00  2.5000000000E-01
>               4.1671769153E+00 -5.1671769153E+00  2.5000000000E-01
>              -5.1671769153E+00 -9.3343538307E+00  7.5000000000E-01
>               9.3343538307E+00  4.1671769153E+00  7.5000000000E-01
>              -4.1671769153E+00  5.1671769153E+00  7.5000000000E-01
>               3.3333333333E-01  6.6666666667E-01  3.9380153023E+00
>              -3.3333333333E-01 -6.6666666667E-01  4.4380153023E+00
>               6.6666666667E-01  3.3333333333E-01 -3.9380153023E+00
>              -6.6666666667E-01 -3.3333333333E-01 -3.4380153023E+00
> ===================================================================================
>  
> 
>     
> 
> 　　　　　　　　
>                 Sincerely Yours，     
> 
> 　　　　　　　　  CHENG Yingchun