Table 2. Data from Absorption Spectra of the HBNGs [9]HBNG, [10]HBNG, and [11]HBNG and of the Monolayer NG ^tBu-HBC in Chloroform.

	λabs/nm (ε/M–1cm–1)a
[9]HBNG	349 (94,600); 373 (136,000); 392 (86,300); 435 (20,600); 502 (6200); and 542 (4700)
[10]HBNG	360 (98,600); 377 (103,900); 415 (38,800); 446 (18,700); 462 (14,400); and 494 (8700)
[11]HBNG	339 (70,800); 377 (125,000); 415 (58,200); 444 (26,100); and 491 (7300)
tBu-HBC	344 (63,750); 360 (141,700); 390 (46,350); 439 (1600); 441 (1650); and 445 (1800)

^aλ_abs/nm (±1 nm) (ε/M^–1 cm^–1) (±10%).