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rgl_potential

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RGL potential

defined in DASSEMBLERS/getforce_classic_RGL.f90

Used form of the interaction and parameters from Riccardo Ferrando:

  • Philos. Mag. A 59 (1989) 321
  • J.Chem.Phys 122 (2005) 194308 R.Ferrando Ag-Cu,Ag-Ni,Au-Cu,Ag-Au,Ag-Pd,Pd-Pt,Ag-Ni

Input file with parameters Cdata/RGL.dat:

 #       [alpha,     p,              q,              A,              dzeta,          ro in bulk, Z (# neigh), cutoff  ]#  cutoff=ro+0.18*sqrt(2)*ro
 #pure metal Co
 #Co-Co=[ 0.5,      9.21000000,     2.97500000,     0.17821769,     1.86943884,     2.50000000, 8,      3.13639609] 

Download the exapmle of RGL.dat file here.

The Pd-Pd clusters are tested with the code of prof. R. Ferrando. The RGL potential is available for: Co,Ni,Cu,Rh,Pd,Ag,Ir,Au,Pt

, and for their bi-metalic alloys: i.e Co-{Ni,Cu,Rh,Pd,Ag,Ir,Pt,Au}, Ni-{Co,Cu,Rh,Pd,Ag,Ir,Pt,Au},Cu-{Co,Ni,Rh,Pd,Ag,Ir,Pt,Au},…

Example: input files and results for Pd-13 cluster

Cdata/usePotential.in:
all Tersoff
freq_of_outputs 5000
Cdata/RGL.in :
fireball.in
&OPTION
basisfile = "in.bas "
lvsfile = "si100.lvs"
kptpreference = "8,8,1"
nstepf = 50
sigmatol = 0.00001
max_scf_iterations = 100
iclassicMD = 1
icluster = 1
iquench = -5
&END

&OUTPUT
iwrtxyz = 1
&END

&QUENCH
&END

&MESH
&END
cgopt.optional
0.10                             ! max. displacement
0.5                              ! scale displacement by this factor if next energy > current energy
0.00001                          ! etot tolerance
0.00001                             ! ftot tolerance
100000                              ! max. number of CG steps
100                                ! max. number of internal iterations
0                                ! refine conjugate gradient results with quenching (0/1 N/Y)
in.bas
13
46     -1.55278940     -0.66307283      4.46770022
46     -3.81059361     -0.02589014      3.46580107
46     -2.26348808     -1.92036421      2.36491842
46      0.29779986     -1.26589646      2.81859863
46     -3.43927526     -2.35925179      4.73547936
46     -1.60461428     -1.97602263      6.65425424
46     -0.90014284     -3.12563464      4.33549742
46      0.70503359     -1.30028077      5.46954441
46      0.33370503      1.03310872      4.19993529
46     -1.50091193      0.64991624      2.28116498
46     -3.40338038     -0.06025942      6.11678710
46     -0.84208126      0.59422287      6.57047660
46     -2.20546930      1.79947105      4.59992343

Results:

Total energy

Type of program: Without cutoff/with cutoff

Fireball: -42.245639500986748/-42.032105248784468

R.Ferrando's code : -42.245638799182252/-42.093188075082516

Both programs give the same geometry and the same energy without cutoff. Both codes use different cutoff: while in Fireball only the contributions of rij<rcutoff are included in Riccardo's code are the contributions from rcutoff2>rij>rcutoff included with coefficient which changes from 1 to 0. The coeficient is 1 rcutoff and ~ (r-rcutof2)**5

Geometry:
fireball:
13
46    -1.56048    -0.66307     4.46770
46    -3.82206    -0.02481     3.46414
46    -2.27238    -1.92245     2.36142
46     0.29321    -1.26688     2.81588
46    -3.45011    -2.36207     4.73592
46    -1.61239    -1.97821     6.65790
46    -0.90673    -3.12972     4.33526
46     0.70110    -1.30134     5.47125
46     0.32915     1.03593     4.19948
46    -1.50856     0.65206     2.27750
46    -3.41417    -0.05927     6.11952
46    -0.84857     0.59630     6.57398
46    -2.21423     1.80357     4.60014
R.Ferrando's code:
13
Pd Pd  -42.093188075082516
Pd     -0.78574300     -5.38066317      1.51796249
Pd     -1.34185576     -5.43042935      4.14151640
Pd      0.90235195     -4.81689921      5.47622212
Pd     -0.09240767     -2.87316513      0.86509517
Pd      1.02985387     -6.31681416      3.25595724
Pd     -0.22001956     -1.37322404      3.08512530
Pd      1.59579548     -2.30937046      4.82342901
Pd      2.15176488     -2.25951287      2.19987508
Pd      2.84537098     -4.38792005      3.67773344
Pd     -2.03552358     -3.30217340      2.66375669
Pd      1.80216905     -4.73619221      1.23133620
Pd      0.40497040     -3.84499042      3.17070313
Pd     -0.99212677     -2.95366942      5.11014275

The biatomical case not yet debugged !

rgl_potential.1286193399.txt.gz · Last modified: 2011/02/18 13:14 (external edit)