Fig. 2: Photophysical properties of Ph-3CP in solutions.
From: Single-component-based multicolor emissions enabled by symmetry breaking
a Molecular structure of reference compounds Ph-3CB (left), Ph-CP (middle) and target compound Ph-3CP (right). α and β correspond to two dihedral angles, respectively. b Emission spectra of Ph-3CP, Ph-3CB, and Ph-CP in toluene (λex = 300 nm). c The excitation spectra of Ph-3CP in toluene (λem = 395–570 nm). d The emission spectra of Ph-3CP in toluene (λex = 290–360 nm). e Boltzmann distributions of Ph-3CP. The structural parameter Δγ is defined as: \(\Delta \gamma=\frac{1}{N}{\sum }_{i}^{N}\left[\left|{\theta }_{i}-{\theta }_{i}^{{C}_{3}}\right|+3\left|{\varphi }_{i}-{\varphi }_{i}^{{C}_{3}}\right|\right]\), where \(\theta\) represents the torsion angle between the central and peripheral benzene rings in triphenylbenzene core, and \(\varphi\) denotes the torsion angle between the central benzene ring and the C–C bond of o-carborane units. These values are extracted from the optimized ground-state geometries of Ph-3CP. A smaller Δγ indicates closer structural resemblance to idealized C3 symmetry. f Superimposed geometries of Ph-3CP illustrating the C3-symmetric conformer (Conf. 9, pink) and the most thermodynamically favored asymmetric conformer (Conf. 1, purple).
