Ground-state total energy differences between trans,anti and cis,syn conformers and between trans,anti and trans,syn conformers, as well as associated Boltzmann populations calculated from the energy differences at 25 °C in vacuum.

Dye	Energy difference (kJ mol−1)		Boltzmann populations (%)
	trans,anti–cis,syn	trans,anti–trans,syn	trans,anti	trans,syn	cis,syn
SQ-(N(CH3)2)2	−4.81	−8.39	84.93	2.88	12.2
SQ-N(CH3)2	−4.78	−8.18	84.58	3.12	12.3
SQ-(CH3)2	−4.77	−8.33	82.14	1.31	16.54
SQ-CH3	−4.76	−8.32	84.65	2.95	12.39
SQ-H2	−4.81	−8.31	82.69	2.57	14.74
SQ-Cl	−4.70	−8.18	80.49	1.49	18.02
SQ-(Cl)2	−4.72	−8.46	83.02	2.54	14.44
SQ-NO2	−4.69	−8.85	84.84	2.38	12.78
SQ-(NO2)2	−4.95	−8.73	85.83	2.53	11.63