Inside Cover, Volume 34, Issue 4

In the study by Łukasz Piȩkoś and Mariusz PawelPaweł Mitoraj on page 294, ab initio Car‐Parrinello molecular dynamics simulations and static DFT calculations are performed to characterize ansa‐bridged molybdocene complexes [(C5H4)2XMe2MoH3]+ for X = C, Si, Ge, Sn, and Pb. The bottom part of the cover presents the crucial role of the size of the ansa‐bridge, XMe2, on the equilibrium of dihydrogen/hydride (H2/H) ↔ trihydride (H3) for molybdocene complexes. The mechanism of breaking of dihydrogen is elucidated by deformation density channels (Δρi) originating from natural orbitals for chemical valence (NOCV) combined with an energy decomposition method (ETS). In the upper part of the image, subsequent dihydrogen bond activation is presented based on NOCVdeformation density channels.