650. N/EDA in GAMESS. 2. Defining an external basis set

This is post number two in a series. Post 1 is here: http://verahill.blogspot.com/2018/06/649-neda-in-gamess-1-recompiling-gamess.html

Defining external basis sets isn't hard, but I find that the gamess documentation isn't great, and there isn't as much online as one would hope.

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1. Either way, I'll create an external basis set file with def2svp and def2tzvp at /opt/gamess/gamess_nbo/EXTFILE.txt

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2. Get the basis set definition from https://bse.pnl.gov/bse/portal -- select the atoms you want, and the basis set, set format to GAMESS US, and click Get Basis Set.

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3. When you paste the data into the EXTFILE.txt,
a) skip the $DATA tag, and
b) change the atom definition to their corresponding symbols (e.g. H instead of Hydrogen) and append the name of the basis set,

so the beginning looks like this:

MG DEF2SVP
S   5
  1   4953.8339196             -0.57778967498E-02      
  2    745.18044154            -0.43124761082E-01      
  3    169.21604972            -0.19268216987    
  4     47.300672019           -0.48641439116    
  5     14.461336973           -0.42550894077    
S   3
  1     24.768174789            0.87956969984E-01      
  2      2.4940945349          -0.55165058128    
  3      0.87807584533         -0.53443294833    
S   1
  1      0.87212782497E-01            1.0000000        
S   1
  1      0.33599293780E-01            1.0000000        
P   5
  1     98.053010494           -0.14480564601E-01      
  2     22.586932277           -0.95495750787E-01      
  3      6.8391509842          -0.30787672651    
  4      2.2332843818          -0.49936292886    
  5      0.71606599387         -0.31503476213    
P   1
  1      0.18914796195          1.0000000        
P   1
  1      0.53768755187E-01            1.0000000        
D   1
  1      0.1010000              1.0000000 

H DEF2SVP
S   3
  1     13.0107010              0.19682158E-01   
  2      1.9622572              0.13796524       
  3      0.44453796             0.47831935       
S   1
  1      0.12194962             1.0000000        
P   1
  1      0.8000000              1.0000000        

C DEF2SVP

and the end like this:

D   1
  1      0.64500000             1.0000000        
F   1
  1      1.42800000             1.0000000        

MG DEF2TZVP
S   7
  1  31438.3495550              0.60912311326E-03      
  2   4715.5153354              0.47066196465E-02      
  3   1073.1629247              0.24135820657E-01      
  4    303.57238768             0.93628959834E-01      
  5     98.626251042            0.26646742093    
  6     34.943808417            0.47890929917    
  7     12.859785199            0.33698490286    
S   3
  1     64.876913004            0.19180889307E-01      
  2     19.725520777            0.90913704392E-01      
  3      2.8951804339          -0.39563756125    
S   2
  1      1.1960454710           1.6827603373     
  2      0.54329451156          0.52141091954    
S   1
  1      0.10099104092          1.0000000        
S   1
  1      0.36865728085E-01            1.0000000        
P   5
  1    179.87189612             0.53799549018E-02      
  2     42.120069376            0.39318014098E-01      
  3     13.120503032            0.15740129476    
  4      4.6257503609           0.35919094128    
  5      1.6695211016           0.45533379310    
P   1
  1      0.58551012105          1.0000000        
P   1
  1      0.18914796195          1.0000000        
P   1
  1      0.53768755187E-01            1.0000000        
D   1
  1      3.4440000              1.0000000        
D   1
  1      0.2900000              1.0000000        
D   1
  1      0.0700000              1.0000000

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4. Edit the gms-files.csh in your gamess root (e.g. /opt/gamess/gamess_nbo)

setenv  EXTBAS /opt/gamess/gamess_nbo/EXTFILE.txt

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5. To use, put

$BASIS EXTFIL=.TRUE. GBASIS=DEF2TZVP $END

or

$BASIS EXTFIL=.TRUE. GBASIS=DEF2SVP $END

in your gamess input file.