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Large Molecule Epitaxy on Single Crystal Metals, Insulators and Single Crystal and MBE-Grown Layered Semiconductors

We review the packing structures for a series of aromatic hydrocarbons, deposited by vacuum deposition methods as ordered monolayers→→multilayers, on a variety of metal, semiconductor and insulator surfaces. New results are presented for the adsorption of monolayers of perylenes, phthalocyanines, coronene, and pentacenes on the Cu(100) surface, along with the implications of these studies for the formation of ordered multilayers of these molecular systems. Aromatic molecules without heteroatoms appear to pack in a flat-lying motif, and exhibit approximately hexagonal close packing, even on a substrate with four-fold symmetry such as Cu(100). In general, aromatic systems whose bulk structures lend themselves to layer-by-layer growth during vacuum deposition appear to be the best candidates for ordered multilayer growth.