6. Constants and Units
HyMD uses the following units and constants internally and in all input and output:
Quantity |
Symbol |
Unit |
|---|---|---|
length |
\(r\) |
\(\text{nm}=10^{-9}~\text{m}\) |
time |
\(t\) |
\(\text{ps}=10^{-12}~\text{s}\) |
charge |
\(q\) |
\(e=1.602176634 \cdot 10^{-19}~\text{C}\) |
mass |
\(m\) |
\(\text{u}=1.66053906660 \cdot 10^{-27}~\text{kg}\) |
temperature |
\(\text{T}\) |
\(\text{K}\) |
energy |
\(E\) |
\(\text{kJ}\,\text{mol}^{-1}\) |
velocity |
\(v\) |
\(\text{nm}\,\text{ps}^{-1}=10^3~\text{m}\,\text{s}^{-1}\) |
momentum |
\(P\) |
\(\text{u}\,\text{nm}\,\text{ps}^{-1}=10^3\text{u}\,\text{m}\,\text{s}^{-1}\) |
force |
\(\mathbf{F}\) |
\(\text{kJ}\,\text{mol}^{-1}\text{nm}^{-1}\) |
pressure |
\(p\) |
\(\text{bar}=100~\text{kPa}\) |
electric potential |
\(\Psi\) |
\(\text{kJ}\,\text{mol}^{-1}\text{nm}^{-1}e^{-1}=0.01036426965~\text{V}\) |
electric field |
\(\mathbf{E}\) |
\(\text{kJ}\,\text{mol}^{-1}\text{nm}^{-1}e^{-1}=1.03642696562 \cdot 10^7~\text{V}\,\text{m}^{-1}\) |
compressibility |
\(\kappa\) |
\(\text{mol}\,\text{kJ}^{-1}\) |
field-interaction |
\(\tilde\chi\) |
\(\text{kJ}\,\text{mol}^{-1}\) |
Constant |
Symbol |
Value |
|---|---|---|
gas constant |
\(R\) |
\(8.3144621\cdot10^{-3}~\text{kJ}\,\text{mol}^{-1}\text{K}^{-1}\) |
Boltzmann’s constant |
\(k_\text{B}\) |
\(8.3144621\cdot10^{-3}~\text{kJ}\,\text{mol}^{-1}\text{K}^{-1}\) |
Avogadro’s constant |
\(N_\text{A}\) |
\(6.02214076 \cdot 10^23~\text{mol}^{-1}\) |
Vacuum permittivity |
\(\varepsilon_0\) |
\(8.85418781281 \cdot 10^{-12}~\text{kg}^{-1}\text{m}^{-3}\text{s}^4\,\text{A}^2\) |
Coulomb constant |
\(k_\text{e}\) |
\(138.935458~\text{kJ}\,\text{mol}^{-1}\text{nm}\,e^{-2}\) |