The Continuum Between Hexagonal Planar and Trigonal Planar Geometries**

New heterometallic hydride complexes that involve the addition of {Mg−H} and {Zn−H} bonds to group 10 transition metals (Pd, Pt) are reported. The side-on coordination a single Pd forms well-defined σ-complex. In contrast, three or Pt results in formation planar with subtly different geometries. We compare their structures through experiment (X-ray diffraction, neutron multinuclear NMR), computational methods (DFT, QTAIM, NCIPlot), theoretical analysis (MO diagram, Walsh diagram). These species can be described as snapshots along continuum bonding between ideal trigonal hexagonal