We have prepared Langmuir-Blodgett monolayers of hexadecylquinolinium tricyanoquinodimethanide (C(16)H(33)Q(+)-3CNQ(-)) on gold surfaces and characterized the structure by surface plasmon resonance (SPR), X-ray. photoelectron spectroscopy (XPS), reflection-absorption infrared spectroscopy (RAIRS), Raman spectroscopy, and water contact angle measurements. We compare the IR and UV-vis spectra Of C(16)H(33)Q(+)-3CNQ(-) to a series of compounds that contain the key functional groups in the titled compound to help assign the spectral features. The surface spectroscopic measurements indicate that the molecules in the monolayer are aligned such that the two terminal cyano groups are adsorbed on the An surface, and that the aliphatic chain is away from that surface. The thickness of the monolayer was measured by XPS to be similar to26 Angstrom and suggests that the molecules are tilted similar to40degrees away from the surface normal. High-resolution XPS and spectroelectrochemical measurements of C(16)H(33)Q(+)-3CNQ(-) strongly suggest that it is a ground-state zwitterion in both the adsorbed and solvated forms.