defined in DASSEMBLERS/getforce_classic_Tersoff.f90

The implementation uses the shape of tersoff potential published in:

• PRB37(1988)6991
• PRB39(1989)5566 (alloys)

(with aij=1)

The parameters of the potential are defined in file Cdata/Tersoff.dat.

• Si, Ge, C, C-Si, Si-Ge (PRB39(1989)5566 + corrections), optimized for bulk or surfaces
• Si, Si-O, O (Computational Materials Science 39 (2007) 334–339), optimized for molecules and clusters
• Si, As clusters ( Vacuum,44(1993)377 )

#       A           B       lambda1 lambda2 lambda3 beta        n       c           d           h       R       ksi     S
C-C =   [1393.6,    346.7,  3.4879, 2.2119, 0.0,    1.5724e-7,  0.72751,3.8049e+4,  4.3484, -0.57058,   1.8,    1.0,    2.1]
Si-Si = [1830.8,    471.18, 2.479,  1.7322, 0.0,    1.1e-6,     0.78734,1.0039e+5,  16.217, -0.59825,   2.7,    1.0,    3.3]
Ge-Ge = [1769.0,    419.23, 2.4451, 1.7047, 0.0,    9.0166e-7,  0.75627,1.0643e+5,  15.652, -43.884,    2.8,    1.0,    3.1 ]
C-Si =  [0.0,       0.0,    0.0,    0.0,    0.0,    0.0,        0.0,    0.0,        0.0,        0.0,    0.0,    0.9776, 0.0]
Ge-Si = [0.0,       0.0,    0.0,    0.0,    0.0,    0.0,        0.0,    0.0,        0.0,        0.0,    0.0,    1.00061,0.0]

You can download the example here

(You must correct the paths to file/directory where symlinks point to).