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Conjugated molecules with a saturated alkyl linker between a thiol docking group and the π-conjugated core have been shown to form self-assembled monolayers (SAMs) with a high degree of long-range order and uniformity. Additionally, pronounced odd−even effects have been observed in a number of properties characterizing these SAMs. We focus on ω-(biphenyl-4-yl)alkanethiols with n = 0−6 −(CH₂)_n− units deposited on Au(111) and investigate the microscopic origin of these odd−even effects in terms of the local sulfur−gold bonding geometry by employing first-principles calculations. An additional structural parameter, the torsion angle between the two phenyl rings in the biphenyl moiety, is identified and its relation to the experimentally observed odd−even effects is discussed. More importantly, we address relevant quantities for the application of these SAMs in molecular electronic devices, in particular, the …