Table 1.
Unit cell parameters for the benzoic acid polymorphs (A, B and C) observed in this study together with those of n-C50 buffer layer. D1 and D2 are the molecular densities of the different polymorphs observed on HOPG and atop n-C50 buffer layer, respectively. θ1 and θ2 are the percentage surface coverages of the respective polymorphs at [BA-OC14] = 9 × 10−5 M (on HOPG) and [BA-OC14] = 3.8 × 10−4 M (n-C50 buffer layer), respectively.
| Unit cell (HOPG) | D1 (molecules/nm2) | θ1 (%) | Unit cell (n-C50 buffer layer) | D2 (molecules/nm2) | θ2 (%) | |||||
| a (nm) | b (nm) | α (°) | a (nm) | b (nm) | α (°) | |||||
| A | 1.8 ± 0.1 | 4.4 ± 0.1 | 81.0 ± 2.7° | 0.74 | 60 | 1.8 ± 0.1 | 4.6 ± 0.1 | 77.9 ± 2.4° | 0.71 | 50 |
| B | 3.4 ± 0.1 | 3.4 ± 0.1 | 86.9 ± 1.3° | 0.68 | 39 | 3.6 ± 0.2 | 3.4 ± 0.1 | 88.2 ± 4.9° | 0.65 | 49 |
| C | 1.7 ± 0.1 | 1.6 ± 0.1 | 79.6 ± 1.0 ° | 0.71 | 1 | 1.5 ± 0.1 | 2.0 ± 0.2 | 83.6 ± 2.7° | 0.68 | 1 |
| n-C50 | 6.6 ± 0.1 | 0.5 ± 0.1 | 90.0 ± 2.0° | – | – | – | – | – | – | – |