Please do not adjust margins Other geometrical features of metallylenes, that change when going down Group 14 to the larger element, are the E-L bond length and the L-E-L angle (E = central Group 14 tetrel atom and L = ligand). The E-L bond length increases with a larger atom E, while the L-E-L angle decreases, as shown in Refs. 28 and 43 when comparing experimentally characterized metallylenes. In the following section, we will discuss why a smaller bite angle can result in a lower HOMO energy, and thus a decreased reactivity. Having examined the effects of transitioning from carbenes to silylenes, germylenes, stannylenes, and plumbylenes, we will now discuss the impact of varying the ligands.