Unit conversions commonly used in computational materials science
| | 国际单位制 | 原子单位制 |
|---|
| 质量 | $kg$ | $m_e=9.1094\times10^{-31}:kg$ |
| 电荷 | $C$ | $e=1.6022\times10^{-19}:C$ |
| 角动量 | $kg\cdot m^2\cdot s^{-1}$ | $\hbar=1.0546\times10^{-43}:J\cdot s$ |
| 介电常数 | $F\cdot m^{-1}$ | $4\pi\varepsilon_0=1.1127\times10^{-10}:F\cdot m^{-1}$ |
| 长度 | $m$ | $a_0=\frac{4\pi\varepsilon_0\hbar^2}{m_ee^2}=5.2918\times10^{-11} :m$ |
| 能量 | $J$ | $\mathscr{E}_a=1 :Hartree = \frac{m_ee^2}{16\pi^2\varepsilon^2\hbar}=4.3597\times10^{-18} :J$ |
Notice: The following is mainly based on the content of Prof. Burkhard Militzer at UC Berkeley, with some corrections.
Pressure:
\[\begin{aligned} & 1 \:eV/\AA^3 = 160.21766208 \:GPa \\ & 1 \:Ha/{Bohr}^3 = 29421.02648438959 \:GPa \\ & 1 \:GPa = 10 \:kbar = 145037.738007218 \:pound/{inch}^2 \\ & 1 \:atm = 1.01325 \:bar = 0.000101325 \:GPa \\ & 1 \:pascal = 1.0 \times 10^{-9} \:GPa \end{aligned}\]Force:
\[\begin{aligned} & 1 \:Ry/Bohr = 25.71104309541616 \:eV/\AA \\ & 1 \:Ha/Bohr = 51.42208619083232 \:eV/\AA \end{aligned}\]Energy:
\[\begin{aligned} & 1 \:Hartree = 2 \:Ryd = 27.211396 \:eV (nist - 27.21138386) \\ & 1 \:kJ/mol = 0.0103642688 \:eV/atom \\ & 1 \:J = 6.24150965\times10^{18} \:eV (CODATA) \\ & 1 \:eV = 1.6021766208\times10^{-19} \:J \end{aligned}\]Length:
\[1 \:Bohr = 0.529177208 \:\AA\]Temperature:
\[\begin{aligned} & 1 \:k_B=3.166815\times10^{-6} \:Ha/K = 8.617343*10^{-5} \:eV/K \\ & 1 \:eV = 1 \:k_BT = 11604.505008 \:K (~10^4 \:K) \end{aligned}\]Chemical Accuracy:
\[\begin{aligned} & 1 \:kcal/mol = 43.36 \:meV/atom \\ & chemical \:accuracy = 1 \:kcal/mol \:or \:4 \:kJ/mol \end{aligned}\]Quantity
\[1 \:mol = 6.02214179 \times 10^{23}\]Frequency
\[1 \:THz = 33.35641 \:cm^{-1} = 4.13567 \:meV\]
