Dipole-dipole forces occur as soon as the positive component of a polar molecule is attracted to the an unfavorable part the a polar molecule. In a nonpolar molecule, there might still be polar bonds, it"s simply that the dipoles publication each various other out. So why can"t over there be dipole-dipole forces in between nonpolar molecules through polar bonds? There are still hopeful and an unfavorable parts of the molecule, for this reason there deserve to be attractions in between them.

For example, in $\ceCO2$, over there are an unfavorable areas close to the oxygens and positive areas near the carbon.

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edited Dec 30 "15 at 4:25

Geoff Hutchison
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Short answer: there are countless electrostatic interactions in between two non-polar molecules.

Beyond monopole (full charges) and permanent dipole moments (polar molecules), there is a full multipole expansion for the electrostatic potential around any type of molecule. (This is technically true because that atoms and also ions too, but higher-order terms room really only advantageous for molecules.)

These terms are crucial - the quadrupole-quadrupole interactions dictate the orientation that the benzene dimer and also $\ceCO2$ dimer in your example.1
$$E(r)=\frac-\Theta_1\Theta_24\pi\epsilon_0r^5\times\Gamma(\theta_1,\theta_2,\phi)$$
So roughly $1/r^5$, contrasted to $1/r^3$ because that dipole-dipole interactions, or $1/r^6$ for dispersion pressures like induced-dipoles.