Revisiting Dual Intramolecular Charge-Transfer Fluorescence of Phenothiazine-triphenyltriazine Derivatives

Abstract

The photophysical properties of the phenothiazine-triphenyltriazine derivative, PTZ-TRZ, are reinvestigated. The results, in combination with the computational approaches, lead us to draw the conclusion that the complicated excitation behavior in toluene (ref ), in part, is due to the UV absorption cutoff region for toluene where the <315 nm excitation is greatly distorted by solvent absorption, i.e., the inner filter effect, in a regular sample cuvette (1.0 cm path length). Switching the solvent to cyclohexane with the UV cutoff wavelength at 235 nm simplifies the results. In cyclohexane, two isomers exist for PTZ-TRZ in the ground state and quasi-axial and quasi-equatorial conformers. Upon electronic excitation, both quasi-axial and quasi-equatorial conformers undergo structural relaxation to an energy minimum state where the phenothiazine is in a planar configuration.

Active uniaxially ordered suspensions on disordered substrates

“…However, due to rotation invariance, the coefficient of all three terms must rescale the same way (which implies χ = 1 − ζ) implying that the exponents calculated above have to be modified by fluctuations. This parallels the situation with only annealed noise [22,30], where the linear exponents (χ = −1/2, ζ = 2) do not satisfy this relationship, but the exact exponents (χ = −1/2, which remains unchanged and ζ = 3/2) do. While I have not been able to calculate the exact exponents for this model, it is reasonable to assume that nonlinearities will not destroy the long-range order in this system with quenched disorder as well.…”

“…x , the small wavevector divergence of |δc q | 2 is weaker than for q ≈ q y ). As in the corresponding annealed noise problem [22,30] and as discussed in the appendix, the nonlinearities in the θ q equation have the forms (q y /q x )(θ 2 ) q , (θ 3 ) q (both with coefficient w), q y (θ 2 ) q , δc q−k k x θ k and q y (δc 2 ) q , while those in the concentration equation have the form q x (δc 2 ) q , q y θ q−k δc k and q x (θ 2 ) q . Using the linear exponents obtained above, I find that the only relevant nonlinearities in the θ q equation are (q y /q x )(θ 2 ) q and (θ 3 ) q , both of which must rescale the same way as the linear (q 2 y /q 2 )θ q term, while concentration equation has only one relevant nonlinearity q x (θ 2 ) q .…”

“…Using the linear exponents obtained above, I find that the only relevant nonlinearities in the θ q equation are (q y /q x )(θ 2 ) q and (θ 3 ) q , both of which must rescale the same way as the linear (q 2 y /q 2 )θ q term, while concentration equation has only one relevant nonlinearity q x (θ 2 ) q . In the annealed noise model, if one ignored the concentration fluctuations, one could obtain the exact static exponents [22,30] through a mapping to a two-dimensional smectic, and ultimately, to a 1 + 1 dimensional KPZ equation [31,32]. However, an equivalent mapping is not available here.…”

Swimmer Suspensions on Substrates: Anomalous Stability and Long-Range Order

“…This implies that our model, in which there is no explicit constraint on p, also has long-range order in two dimensions with the same roughness and anisotropy exponents as in Ref. [32]. This relation between the nonlinear theory of polar swimmers without number conservation in incompressible polar fluid and a theory of a suspension of polar active particles with ∇ · p = 0 is unusual; for instance, an apolar system in an incompressible fluid described in [9] does not correspond to a theory in which ∇∇ : Q = 0, where Q is the apolar order parameter.…”

“…In this simple case, our model exactly maps onto the polar flock with constraint ∇ · p = 0 studied in Ref. [32]. This mapping ultimately yields exact equal-time exponents of the ordered phase via a transformation to the KPZ equation [26].…”