Up to now, only single-molecule adsorption has been discussed. However, maximum coverage is a crucial factor for interface formation. The coverage is studied using the most stable adsorption site, 6-4 (Figure ). The cell size is halved in both directions; hence the molecules are added in 0.125 steps for the coverage θ. We investigated the energetic contributions related to the coverage of 0.125 using pEDA to rationalize the trends. For the coverage, the adsorption energy Eads(n) is used (eq. 7). Thus, for A an adsorption energy Eads(1) = -146 kJ mol -1 is observed for a coverage θ = 0.125. For the single COC adsorption (equal to 0.0625), an adsorption energy of Eads= -140 kJ mol -1 shows that increasing the coverage slightly stabilizes the interaction by Figure . relative Contributions ΔΔE to the chemical bonding terms relative to the coverage of 0.125 (eq. 8). The adsorption energy is calculated using PBE-D3/TZ2P. 6 kJ mol -1 . For θ = 0.25, the adsorption energy of the second COC adsorbate is either Eads(2) = -135 kJ mol -1 , -44 kJ mol -1 or +45 kJ mol -1 depending on the adsorption site. The most favorable adsorption is a second COC placed as far away as possible from the first adsorbate resulting in every second 4-ring occupied with one COC (-135 kJ mol -1 ) in a checkerboard pattern (B). The second COC in the same 6-4-row is least favorite (45 kJ mol -1 ). Every second 4-ring in one 6-4-row (D) and adjacent in 8-4-direction (C) is still possible (-44 kJ mol -1 ), but far less favorable than B (-135 kJ mol -1 ). Due to the large difference of 91 kJ mol -1 between B and C, a prevalence of B can be expected.