ExTeP potential file header update

# B and N mixture, parameterized for Tersoff potential

# values are from Albe et.al - Rad. Eff. Def. Sol. 141 (1997) 85.                                                                                                     

#values are calculated from Albe et. al from                                                                                                                          

# m = 3                                                                                                                                                               

# gamma = 1                                                                                                                                                           

# c = c, d=d                                                                                                                                                          

# cos(thetat0) = h                                                                                                                                                    

# n = n                                                                                                                                                               

# beta = gamma_albe                                                                                                                                                   

# lambda1=beta_albe*sqrt(2*S_albe)                                                                                                                                    

# lambda2=beta_albe*sqrt(2/S_albe)                                                                                                                                    

# lambda3=lambda3                                                                                                                                                     

# A=D0/(S-1)*exp(lambda1*r0)                                                                                                                                          

# B=S*D0/(S-1)*exp(lambda2*r0)                                                                                                                                        

# R = R, D=D                                                                                                                                                          

# values are from Los et al. PhysRevB.96.184108 (2017)

# Tersoff parameters for various elements and mixtures

# multiple entries can be added to this file, LAMMPS reads the ones it needs