Table 1. Low-energy absorption and fluorescence band maxima, FWHM values, Stokes shifts, and integrated absorptive oscillator strengths for PM-Sp-PM chromophores over the 600–1000 nm wavelength range.
Chromophores |
λ
max/nm (FWHM/cm–1) |
Stokes shift a /cm–1 | Oscillator strength in red-to-NIR b | |
S0 → S1 | S1 → S0 | |||
ArPZnE-TDQ-EArPZn | 839 (2510) | 995 (1778) | 1869 | 0.827 |
ArPZnE-BTD-EArPZn | 689 (1180) | 741 (1382) | 1019 | 0.455 |
ArPPtE-TDQ-EArPPt | 715 (2415) | 810 (1530) | 1640 | 0.686 |
ArPPtE-BTD-EArPPt | 603 (1061) | 629 (1579) | 686 | 0.168 |
Rf3PZnE-TDQ-ERf3PZn | 705 (1163) | 750 (1370) | 851 | 0.451 |
Rf3PZnArPPtE-TDQ-EArPPtRf3PZn | 755 (1738) | 813 (1432) | 945 | 1.809 |
aStokes shift corresponds to the energy difference between the low-energy transition (Qx) absorption and fluorescence maxima.
bIntegrated oscillator strengths (f) were calculated based on the following expression: , where ε is the experimental extinction coefficient, and ν is the energy (in wave numbers) of the absorption. Oscillator strengths were calculated over the following spectral domains: ArPZnE-TDQ-EArPZn (600–1000 nm); ArPZnE-BTD-EArPZn (600–800 nm); ArPPtE-TDQ-EArPPt (600–850 nm); ArPPtE-BTD-EArPPt (600–700 nm); Rf3PZnE-TDQ-ERf3PZn (600–850 nm); Rf3PZnArPPtE-TDQ-EArPPtRf3PZn (600–950 nm).