For applications such as electronics, the physical properties of diamond can be modified by introducing trigonal C(sp 2 ) -double C=C bonds as in ethene -and linear C(sp 1 ) -triple CC bonds as in acetylene -on the one hand, and by working on the particle size as in nanodiamonds, on the other hand. Indeed, recent works have shown that nanodiamonds with mixed C(sp 2 )-C(sp 3 ) hybridization play an important role in designing advanced electronic materials . electrochemical applications of hybrid diamond/sp 2 -C nanostructures . Furthermore, regarding other mixed carbon hybridizations, sp 3 -sp 1 were recently identified in superhard so-called "ynediamond", which is classified as semi-metallic .