DL POLY

DL_POLY is a general purpose serial and parallel molecular dynamics simulation package developed at Daresbury Laboratory by W. Smith, T.R. Forester and I.T. Todorov. DL_POLY employs an interesting set of units which have molecular relevance:

physical quantity	symbol	unit value
time	$t_0$	$1\times 10^{-12}$ seconds (picoseconds)
length	$l_0$	$1\times 10^{-10}$ metres (Angstroms)
mass	$m_0$	$1.66054\times 10^{-27}$ kilograms (amu)
charge	$q_0$	$1.60218\times 10^{-19}$ Coulombs (electron charge)
energy	$E_0=m_0(l_0/t_0{)}^2$	$1.66054\times 10^{-23}$ Joules = 10 J mol${-1}^{}$
pressure	$p_0=E_0/l_0^3$	$1.66054\times 10^7$ Pascal = 166.054 bar
Planck constant	$\hslash$	$6.35078E_0{t}_0$
Boltzmann constant	$k_B$	$0.83145E_0/K$

References

1. W. Smith, C. W. Yong and P. M. Rodger "DL_POLY: application to molecular simulation", Molecular Simulation 28 pp. 385-471 (2002)