feos.dft.ExternalPotential.DoubleWell¶
- static ExternalPotential.DoubleWell(sigma_ss, epsilon1_k_ss, epsilon2_k_ss, rho_s)¶
Double well potential
\[V_i^\mathrm{ext}(z)=\mathrm{min}\left(\frac{2\pi}{45} m_i\varepsilon_{2si}\sigma_{si}^3\rho_s\left(2\left(\frac{2\sigma_{si}}{z}\right)^9-15\left(\frac{2\sigma_{si}}{z}\right)^3\right),0\right)+\frac{2\pi}{45} m_i\varepsilon_{1si}\sigma_{si}^3\rho_s\left(2\left(\frac{\sigma_{si}}{z}\right)^9-15\left(\frac{\sigma_{si}}{z}\right)^3\right),~~~~\varepsilon_{1si}=\sqrt{\varepsilon_{1ss}\varepsilon_{ii}},~~~~\varepsilon_{2si}=\sqrt{\varepsilon_{2ss}\varepsilon_{ii}},~~~~\sigma_{si}=\frac{1}{2}\left(\sigma_{ss}+\sigma_{ii}\right)\]- Parameters:
sigma_ss (float) – Segment diameter of the solid.
epsilon1_k_ss (float) – Energy parameter of the first well.
epsilon2_k_ss (float) – Energy parameter of the second well.
rho_s (float) – Density of the solid.
- Return type: