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For many large molecule adlayers, including a number of organic and metal–organic species, the energy level align-ment of the adsorbate with respect to a conducting substrate Fermi level or adjacent layer chemical potential is depen-dent on the interfacial electronic structure and interfacial di-pole layer, as has been demonstrated for a number of molec-ular species [1–3], including the metal (II) phthalocyanines (MPc) [4, 5]. The metal (II) phthalocyanines offer a family of compounds where the d-electron filling of the metal center atom can be systematically altered, without changing the apparent preferential bonding orientation on Au(111) [6, 7]. This persistent orientation with the molecular plane paral-lel with the substrate for very thin films of adsorbed MPc species [6, 7] is unlike the case for the macrocyclic metal center tetraazaannulenes (TMTAA) [8]. If the interface di