Table 1. Summary of cavity sizes (d), binding constants (K_a) and binding energies (E).

	d 1 a Å	d 2 b Å	K a c M–1	E Exp d kJ mol–1	d Calc e	E Calc f kJ mol–1
BB	6.80	6.90	39 000 ± 5000	–26.2	6.71	–102.2
ThBB	6.10	6.72	170000 ± 60 000	–29.9	6.35	–103.7
DThBB	5.80	6.56	67 000 ± 3800	–27.5	5.98	–100.4
mpBB	5.94	6.62	8900 ± 1300	–22.5	5.73	–95.1
PyBB	5.65	—	7400 ± 600	–22.1	5.50	–91.2

^aCentroid-to-centroid distances of BIPY²⁺ units in tetracationic cyclophanes according to solid-state structures.

^bCentroid-to-centroid distances of BIPY˙⁺ units in bisradical dicationic cyclophanes according to solid-state structures.

^cBinding constants of the trisradical triscationic complexes from vis/NIR titrations.

^dBinding energies of the trisradical triscationic complexes calculated from vis/NIR titrations.

^eCentroid-to-centroid distances of BIPY˙⁺ units in bisradical dicationic cyclophanes according to B3LYP-D3-optimized structures solvated in acetonitrile.

^fB3LYP-D3 method calculated binding energies of the trisradical triscationic complexes.