I was wondering whether anyone has demonstrated that a liquid will have a higher boiling point if it is placed in a very large electric field. I believe to be the case, since induced dipoles would be formed and dipoles would more heavily align, but I was wondering if there was any actual experimental evidence and how exactly boiling point grows with temperature.

For an order-of-magnitude check, I set up a model to predict the increase in boiling point.

We have the following formulae (considering induced dipoles only):

\begin{align} U&=-k\frac{p^2}{r^3}N_A\\ p&=\alpha E\\ r&\approx\left(N_A\rho_m\right)^{-\frac{1}{3}} \end{align}

Which gives


Given a change in molar density from $\rho_l$ to the ideal gas $\frac{P}{RT}$, we have

$$\Delta U=k\alpha^2N_A^2E^2\left(\rho_l-\frac{P}{RT}\right)=C_p\Delta T_{\text{boiling}}$$

In the case of benzene (initial boiling point $353.2\,\text{K}$, molar density $11385\,\text{mol m}^{-3}$, specific heat capacity $103\,\text{J mol}^{-1}\text{K}^{-1}$, dielectric strength $163\,\text{MV m}^{-1}$, polarizability $69.6\text{Å}^3$), my model would give a maximum $\Delta U$ of $59.0\,\text{J mol}^{-1}$ before dielectrib breakdown, or $\Delta T_{\text{boiling}}$ of $0.522\,\text{K}$, something that should be measurable. My model probably doesn't take into account a lot of things, but I'm sure that the actual maximum change in boiling point should only be half an order of magnitude away from my estimate hopefully.



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