Supplementary information (ESI) for Phys. Chem. Chem. Phys. This journal is (c) the Owner Societies 2008 This file contains Cartesian coordinates for Di, Cy, Di/Di, Cy/Cy, Di/Cy, Tz/Tz and Tz/Bz optimized at the MP2/DZP++ level of theory. Di C 0.00000000 0.00000000 0.69232000 C 0.00000000 0.00000000 -0.69232000 C 0.00000000 0.00000000 1.92741600 C 0.00000000 0.00000000 -1.92741600 H 0.00000000 0.00000000 2.99804000 H 0.00000000 0.00000000 -2.99804000 Cy C 0.6956842407 0.0000000000 0.0000000000 C -0.6956842407 0.0000000000 0.0000000000 N 1.8886357750 0.0000000000 0.0000000000 N -1.8886357750 0.0000000000 0.0000000000 Di/Di C -0.07341700 1.71353300 0.00000000 C 1.28546800 1.97312200 0.00000000 C -1.28546800 1.47389300 0.00000000 C 2.49902300 2.20666500 0.00000000 C -1.28546800 -1.97312200 0.00000000 C 0.07341700 -1.71353300 0.00000000 C -2.49902300 -2.20666500 0.00000000 C 1.28546800 -1.47389300 0.00000000 H -3.54650500 -2.42846400 0.00000000 H 2.33475100 -1.26177000 0.00000000 H -2.33475100 1.26177000 0.00000000 H 3.54650500 2.42846400 0.00000000 Cy/Cy C 0.5483608130 1.6645431609 0.0000000000 C 1.9350277751 1.7733567164 0.0000000000 C -1.9350277751 -1.7733567164 0.0000000000 C -0.5483608130 -1.6645431609 0.0000000000 N -3.1235996933 -1.8777924126 0.0000000000 N 0.6407287091 -1.5665637536 0.0000000000 N 3.1235996933 1.8777924126 0.0000000000 N -0.6407287091 1.5665637536 0.0000000000 Di/Cy C -1.383366 -1.580150 0.000000 N -2.573189 -1.493566 0.000000 C 0.002845 -1.693951 0.000000 N 1.190764 -1.811095 0.000000 C 1.382396 1.623708 0.000000 C 0.000000 1.675455 0.000000 C 2.616316 1.566959 0.000000 H 3.685989 1.517225 0.000000 C -1.235427 1.716304 0.000000 H -2.305595 1.765452 0.000000 Tz/Tz N 0.850330 -1.353190 1.198482 C 1.353946 -1.005975 0.000000 N 0.850330 -1.353190 -1.198482 C -0.249243 -2.127167 -1.128067 N -0.846117 -2.551023 0.000000 C -0.249243 -2.127167 1.128067 H 2.250018 -0.385068 0.000000 H -0.694242 -2.441657 -2.072074 H -0.694242 -2.441657 2.072074 N 0.262672 2.175871 1.199399 C 0.744699 2.550363 0.000000 N 0.262672 2.175871 -1.199399 C -0.800105 1.354622 -1.129453 N -1.380139 0.906607 0.000000 C -0.800105 1.354622 1.129453 H 1.599336 3.226856 0.000000 H -1.229407 1.019556 -2.073363 H -1.229407 1.019556 2.073363 Bz/Tz C -2.081902 1.625544 0.000000 C -1.379620 1.615231 1.216715 C 0.025611 1.592334 1.217341 C 0.727415 1.579430 0.000000 C 0.025611 1.592334 -1.217341 C -1.379620 1.615231 -1.216715 H -3.171530 1.641508 0.000000 H -1.925060 1.627641 2.160472 H 0.572313 1.582802 2.160365 H 1.817218 1.565443 0.000000 H 0.572313 1.582802 -2.160365 H -1.925060 1.627641 -2.160472 N -0.707486 -1.600571 0.000000 C 0.025611 -1.594167 -1.127298 N 1.369439 -1.605811 -1.198632 C 1.979752 -1.618456 0.000000 N 1.369439 -1.605811 1.198632 C 0.025611 -1.594167 1.127298 H -0.520159 -1.587030 -2.070512 H 3.069569 -1.648315 0.000000 H -0.520159 -1.587030 2.070512