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Ultrahigh vacuum (UHV)-deposited films of the mixed phase of tetramethoxypyrene and tetracyanoquinodimethane on gold have been studied using ultraviolet photoelectron spectroscopy (UPS), x-ray diffraction (XRD), infrared (IR) spectroscopy, and scanning tunneling spectroscopy (STS). The formation of an intermolecular charge-transfer (CT) compound is evident from the appearance of new reflexes in XRD ( and ). A softening of the CN stretching vibration (redshift by ) of TCNQ is visible in the IR spectra, being indicative of a CT on the order of from TMP to TCNQ in the complex. Characteristic shifts in the electronic level positions occur in UPS and STS that are in reasonable agreement with the prediction of density-functional theory (DFT) calculations (GAUSSIAN03 with hybrid functional B3LYP). STS reveals a highest occupied molecular orbital (HOMO)-lowest …