Standards models of dust in the diffuse interstellar medium adopt different size distributions \citep{Mathis77,Greenberg83} and explain the mean dust extinction of the Milky Way by adopting grains at radii below $\sim 250$\,nm (e.g. citep{Mathis77, Desert90, Mathis90, S92, Dwek97, WD01, DraineLi01, DraineLi07, Das10, Draine09, Compiegne11, S14, Jones17, V16, Guillet18.} --- microsized grains have been studied by \cite{43, 44} and used in models by \citeOrmel11, 49, W15b, Draine21, Ysard et al. 2024}