Chlorophyll triplet states in thylakoid membranes of Acaryochloris marina. Evidence for a triplet state sitting on the photosystem I primary donor populated by intersystem crossing.

Photo-induced triplet states in the thylakoid membranes isolated from the cyanobacterium Acaryocholoris marina, that harbours Chlorophyll (Chl) d as its main chromophore, have been investigated by Optically Detected Magnetic Resonance (ODMR) and time-resolved Electron Paramagnetic Resonance (TR-EPR). Thylakoids were subjected to treatments aimed at poising the redox state of the terminal electron transfer acceptors and donors of Photosystem II (PSII) and Photosystem I (PSI), respectively. Under ambient redox conditions, four Chl d triplet populations were detectable, identifiable by their characteristic zero field splitting parameters, after deconvolution of the Fluorescence Detected Magnetic Resonance (FDMR) spectra. Illumination in the presence of the redox mediator N,N,N',N'-Tetramethyl-p-phenylenediamine (TMPD) and sodium ascorbate at room temperature led to a redistribution of the triplet populations, with T3 (|D|= 0.0245 cm-1, |E|= 0.0042 cm-1) becoming dominant and increasing in intensity with respect to untreated samples. A second triplet population (T4, |D|= 0.0248 cm-1, |E|= 0.0040 cm-1) having an intensity ratio of about 1:4 with respect to T3 was also detectable after illumination in the presence of TMPD and ascorbate. The microwave-induced Triplet-minus-Singlet spectrum acquired at the maximum of the |D|-|E| transition (610 MHz) displays a broad minimum at 740 nm, accompanied by a set of complex spectral features that overall resemble, despite showing further fine spectral structure, the previously reported Triplet-minus-Singlet spectrum attributed to the recombination triplet of PSI reaction centre, 3 P 740 [Schenderlein M, Çetin M, Barber J, et al. Spectroscopic studies of the chlorophyll d containing photosystem I from the cyanobacterium Acaryochloris marina. Biochim Biophys Acta 1777:1400-1408]. However, TR-EPR experiments indicate that this triplet displays an eaeaea electron spin polarisation pattern which is characteristic of triplet sublevels populated by intersystem crossing rather than recombination, for which an aeeaae polarisation pattern is expected instead. It is proposed that the observed triplet, which leads to the bleaching of the P740 singlet state, sits on the PSI reaction centre.

Near-IR-Absorbing Bis-Donor Functionalized Aza-BODIPY Derivatives: Synthesis and Photophysical Study by Using Transient Optical Spectroscopy.

A series of near-IR absorbing 2,6-diarylated BF2-chelated aza-boron-dipyrromethenes (aza-BDPs) derivatives bearing different electron donors (benzene, naphthalene, phenanthrene, phenothiazine and carbazole) were designed and synthesized. The effect of different electron donor substitutions on the photophysical properties was studied by steady-state UV-vis absorption and fluorescence spectra, electrochemical, time-resolved nanosecond transient absorption (ns-TA) spectroscopy and theoretical computations. The UV-vis absorption spectra of AzaBDP-PTZ and AzaBDP-CAR (λabs=710 nm in toluene) showed a bathochromic absorption profile compared with the reference AzaBDP-Ph (λabs=685 nm in toluene), indicating the non-negligible electronic interaction at the ground state between donor and acceptor moieties. Moreover, the fluorescence is almost completely quenched for AzaBDP-PTZ/AzaBDP-CAR (fluorescence quantum yield, ΦF=0.2-0.7 % in toluene) as compared with the AzaBDP-Ph (ΦF=27 % in toluene). However, the apparent intersystem crossing ability of these compounds is poor, based on the singlet oxygen quantum yield (ΦΔ=0.3-1.5 %). The ns-TA spectral study showed typical Bodipy localized triplet state transient features, short-lived excited triplet state for AzaBDP-Ph (τT=53.2 µs) versus significantly long-lived triplet state for AzaBDP-CAR (τT=114 µs) was observed under deaerated experimental conditions. These triplet state lifetimes are much longer than that obtained with diiodoAzaBDP (intramolecular heavy atom effect, τT=1.5~7.2 µs). These information are useful for molecular structure design of triplet photosensitizers, for which longer triplet state lifetimes are usually desired. Theoretical computations displayed that the triplet state is mainly localized on the AzaBDP core, moreover, it was found that the HOMO/LUMO energy gap decreased after introducing donor moieties to the skeleton as compared with the reference.

Role of Triplet States in the Photolysis of Proteogenic Amino Acids.

This investigation delves into the UV photodissociation of pivotal amino acids (Alanine, Glycine, Leucine, Proline, and Serine) at 213 nm, providing insights into triplet-state deactivation pathways. Utilizing a comprehensive approach involving time-dependent density functional calculations (TD-DFT), multi-configurational methods, and ab-initio molecular dynamics (AIMD) simulations, we scrutinize the excited electronic states (T1 , T2 , and S1 ) subsequent to 213 nm excitation. Our findings demonstrate that α-carbonyl C-C bond-breaking in triplet states exhibits markedly lower barriers than in singlet states (below 5.0 kcal mol-1 ). AIMD simulations corroborate the potential involvement of triplet states in amino acid fragmentation, underscoring the significance of accounting for these states in photochemistry. Chemical bonding analyses unveil distinctive patterns for S1 and T1 states, with the asymmetric redistribution of electron density characterizing the C-C breaking in triplet states, in contrast to the symmetric breaking observed in singlet states. This research complements recent experimental discoveries, enhancing our comprehension of amino acid reactions in the interstellar medium.

Solvent and alkyl substitution effects on charge-transfer mediated triplet state generation in BODIPY dyads: a combined computational and experimental study.

Donor-acceptor dyads based on BODIPYs have been recently employed to enhance the formation of triplet excited states with the process of spin-orbit charge transfer intersystem crossing (SOCT-ISC) which does not require introduction of transition metals or other heavy atoms into the molecule. In this work we compare two donor-acceptor dyads based on meso-naphthalenyl BODIPY by combining experimental and computational investigations. The photophysical and electrochemical characterization reveals a significant effect of alkylation of the BODIPY core, disfavoring the SOCT-ISC mechanism for the ethylated BODIPY dyad. This is complemented with a computational investigation carried out to rationalize the influence of ethyl substituents and solvent effects on the electronic structure and efficiency of triplet state population via charge recombination (CR) from the photoinduced electron transfer (PeT) generated charge-transfer (CT) state. Time dependent-density functional theory (TD-DFT) calculations including solvent effects and spin-orbit coupling (SOC) calculations uncover the combined role played by solvent and alkyl substitution on the lateral positions of BODIPY.

Extended voltage imaging in cardiomyocytes with a triplet state quencher-stabilized silicon rhodamine.

Voltage imaging of cardiac electrophysiology with voltage-sensitive dyes has long been a powerful complement to traditional methods like patch-clamp electrophysiology. Chemically synthesized voltage sensitive fluorophores offer flexibility for imaging in sensitive samples like human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs), since they do not require genetic transformation of the sample. One serious concern for any fluorescent voltage indicator, whether chemically synthesized or genetically encoded, is phototoxicity. We have been exploring self-healing fluorophores that use triplet state quenchers (TSQs) as a means to reduce the already low phototoxicity of VoltageFluor dyes developed in our lab. We previously showed that conjugation of the TSQ cyclooctatetraene (COT) to a fluorescein based VoltageFluor dye substantially reduced phototoxicity. Here, we show that this approach can be applied to far-red Silicon rhodamine dyes. COT-conjugated Si-rhodamines show improved photostability and reduced phototoxicity in hiPSC-CMs compared to the unmodified dye. This enables imaging of hiPSC-CMs for up to 30 min with continuous illumination. We show that this effect is mediated by a combination of reduced singlet oxygen production and lower loading in the cellular membrane. We discuss future applications and avenues of improvement for TSQ-stabilized VoltageFluor dyes.

Triplet-Induced Singlet Oxygen Photobleaches Near-Infrared Dye-Sensitized Upconversion Nanosystems.

The rapid photobleaching of near-infrared (NIR) dye-sensitized upconversion nanosystems is one of the crucial problems that has blocked their technological applications. Uncovering the photophysical and photochemical pathways of NIR dyes would help to elucidate the photobleaching mechanism and thereby improve the photostability of the system. Here we investigate the triplet dynamics of NIR dyes and their interaction with triplet oxygen in the typically investigated IR806-sensitized upconversion nanoparticle (UCNP) nanosystem. Low-temperature fluorescence at 77 K provides direct proof of the generation of singlet oxygen (1O2) under 808 nm laser irradiation. Mass spectrometry indicates that all three double bonds in the structure of IR806 can be broken in the photochemical process. Coupling IR806 to the surface of UCNPs can accelerate its triplet dynamics, thus producing more 1O2 to photocleave IR806. Importantly, we find that the addition of ß-carotene can scavenge the generated 1O2, thereby providing a simple method to effectively inhibit photobleaching.

Cobalt-Catalyzed Bis-Borylation of Quinolines: The Importance of the Cobalt Triplet State.

We report herein a mild stereo- and regioselective dearomatization of quinolines using the simple low valent HCo(N2 )(PPh3 )3 complex that exhibits labile ligands. Conditions to form selectively, at room temperature, high-valued 1,4-bis-borylated tetrahydroquinolines from simple starting heteroaromatic compounds have been developed. The efficient and selective functionalization of a large scope of quinolines bearing various electron-donating or electron-withdrawing substituents is presented, as well as the post-modification of the resulting C-B bond. NMR and labelling studies are consistent with a cascade mechanism pathway, starting from an in situ generated paramagnetic bis-quinoline cobalt(I) hydride complex. A first quinoline dearomatization followed by a cobalt(I)-catalyzed Markovnikov hydroboration of the remaining double bond allows the introduction of the boronic ester group only at C4 position. DFT calculations particularly highlight the importance of the cobalt triplet state throughout the reaction pathway, and bring some rationalization for the observed C4 selective borylation.

Sparkling Organic Phosphorescence from Fluorinated Tetrathia[7]helicenes: Synthesis and Photophysical, Electrochemical and Computational Studies.

Structure-property correlations in the thiahelicene family are often not trivial beacuse most of the functional groups present on the helical scaffold modify the conjugation size of the π-system. Selecting fluorine-containing groups to provide strong inductive effects without interacting with low-lying orbitals of the system could be the way to overcome the issue. Here we report a study on three fluorine-functionalized tetrathia[7]helicenes, highlighting interesting correlations between the position of the functional groups and the conjugated skeleton properties. Helicenes Heli-F2 and Heli-CF-F2 were prepared by photoinduced isomerization-electrocyclization (the Mallory photocyclization) of the corresponding fluorinated benzodithienyl-ethenes Alk-F2 and Alk-CF-F2, which were prepared in high yields through stereo-conservative Stille reaction. Notably these helicenes were found to display green phosphorescence around 530-550 nm, and the studies suggest an efficient spin-orbit coupling mechanism in these high-energy triplet nonplanar conjugated molecules. Both helicenes and their precursors were thoroughly characterized by means of optical and electrochemical measurements, while DFT calculations enable a rationale on their structure-property correlations to be defined.

Long-Lived Charge Separated States in Anthraquinone-Phenothiazine Dyads: Synthesis and Study of the Photophysical Property by Using Transient Optical and Magnetic Resonance Spectroscopies.

In order to obtain long-lived charge separated (CS) states in electron donor-acceptor dyads, herein we prepared a series of anthraquinone (AQ)-phenothiazine (PTZ) dyads, with adamantane as the linker. UV-vis absorption spectra show negligible electronic interaction between the AQ and PTZ units at ground state, yet charge transfer (CT) emission bands were observed. Nanosecond transient absorption shows that the 3 AQ state is populated upon photoexcitation for AQ-PTZ in cyclohexane (CHX), but in acetonitrile (ACN) a 3 CS state is formed. Similar results were observed for AQ-PTZ-M. The 3 CS state lifetimes were determined as 0.52 µs and 0.49 µs, respectively. Upon oxidation of the PTZ unit, the 3 AQ state was observed in both polar and non-polar solvents. For AQ-PTZ, femtosecond transient absorption spectra show fast formation of the 3 AQ state in all solvents, with no charge separation in CHX, while formation of the 3 CS state takes 106 ps in ACN. For AQ-PTZ-M, a 3 CS state is formed in CHX within 241 ps. Time-resolved electron paramagnetic resonance (TREPR) spectra show that a radical ion pair with electron exchange energy of |2 J|≥5.68 mT was observed for AQ-PTZ and AQ-PTZ-M, whereas in the dyads with the PTZ unit oxidized, only the 3 AQ state was observed.

The photophysics of 2-cyanoindole probed by femtosecond spectroscopy.

The photophysics of 2-cyanoindole (2-CI) in solution (water, 2,2,2-trifluoroethanol, acetonitrile' and tetrahydrofuran) was investigated by steady-state as well as time resolved fluorescence and absorption spectroscopy. The fluorescence quantum yield of 2-cyanoindole is strongly sensitive to the solvent. In water the quantum yield is as low as 4.4 × 10-4. In tetrahydrofuran, it amounts to a yield of 0.057. For 2-CI dissolved in water, a bi-exponential fluorescence decay with time constants of ∼1 ps and ∼8 ps is observed. For short wavelength excitation (266 nm) the initial fluorescence anisotropy is close to zero. For excitation with 310 nm it amounts to 0.2. In water, femtosecond transient absorption reveals that the fluorescence decay is solely due to internal conversion to the ground state. In aprotic solvents, the fluorescence decay takes much longer (acetonitrile: ∼900 ps, tetrahydrofuran: ∼2.6 ns) and intersystem crossing contributes.

Photochemical Transformation of Free Chlorine Induced by Triplet State Dissolved Organic Matter.

Photolysis of free chlorine is an increasingly recognized approach for effectively inactivating microorganisms and eliminating trace organic contaminants. However, the impact of dissolved organic matter (DOM), which is ubiquitous in engineered water systems, on free chlorine photolysis is not yet well understood. In this study, triplet state DOM (3DOM*) was found to cause the decay of free chlorine for the first time. By using laser flash photolysis, the scavenging rate constants of triplet state model photosensitizers by free chlorine at pH 7.0 were determined to be in the range of (0.26-3.33) × 109 M-1 s-1. 3DOM*, acting as a reductant, reacted with free chlorine at an estimated reaction rate constant of 1.22(±0.22) × 109 M-1 s-1 at pH 7.0. This study revealed an overlooked pathway of free chlorine decay during UV irradiation in the presence of DOM. Besides the DOM's light screening ability and scavenging of radicals or free chlorine, 3DOM* played an important role in the decay of free chlorine. This reaction pathway accounted for a significant proportion of the decay of free chlorine, ranging from 23 to 45%, even when DOM concentrations were below 3 mgC L-1 and a free chlorine dose of 70 µM was present during UV irradiation at 254 nm. The generation of HO• and Cl• from the oxidation of 3DOM* by free chlorine was confirmed by electron paramagnetic resonance and quantified by chemical probes. By inputting the newly observed pathway in the kinetics model, the decay of free chlorine in UV254-irradiated DOM solution can be well predicted.

Preparation of Xanthene-TEMPO Dyads: Synthesis and Study of the Radical Enhanced Intersystem Crossing.

We prepared a rhodamine-TEMPO chromophore-radical dyad (RB-TEMPO) to study the radical enhanced intersystem crossing (REISC). The visible light-harvesting chromophore rhodamine is connected with the TEMPO (a nitroxide radical) via a C-N bond. The UV-vis absorption spectrum indicates negligible electron interaction between the two units at the ground state. Interestingly, the fluorescence of the rhodamine moiety is strongly quenched in RB-TEMPO, and the fluorescence lifetime of the rhodamine moiety is shortened to 0.29 ns, from the lifetime of 3.17 ns. We attribute this quenching effect to the intramolecular electron spin-spin interaction between the nitroxide radical and the photoexcited rhodamine chromophore. Nanosecond transient absorption spectra confirm the REISC in RB-TEMPO, indicated by the detection of the rhodamine chromophore triplet excited state; the lifetime was determined as 128 ns, which is shorter than the native rhodamine triplet state lifetime (0.58 µs). The zero-field splitting (ZFS) parameters of the triplet state of the chromophore were determined with the pulsed laser excited time-resolved electron paramagnetic resonance (TREPR) spectra. RB-TEMPO was used as a photoinitiator for the photopolymerization of pentaerythritol triacrylate (PETA). These studies are useful for the design of heavy atom-free triplet photosensitizers, the study of the ISC, and the electron spin dynamics of the radical-chromophore systems upon photoexcitation.

Photonics of Some Monomethine Cyanine Dyes in Solutions and in Complexes with Biomolecules.

In search of new probes for biomolecules, the spectral fluorescent study of four monomethine cyanine dyes (MCD), both unsymmetrical and symmetrical, has been carried out in different organic solvents, in aqueous buffer solutions, and in the presence of DNA and HSA. The complexation of MCD with biomacromolecules leads to a steep growth of the fluorescence intensity. Complexes of MCD with dsDNA and HSA of various types were modeled in silico by molecular docking. Experiments on thermal dissociation of dsDNA in the presence of MCD showed the formation of intercalative complexes of MCD with DNA. Quenching of intrinsic fluorescence of HSA by MCD occurred with rate constants much higher than the diffusion limit, that is, in dye-HSA complexes. Effective constants of MCD complexation with the biomacromolecules were estimated. MCD 1 has the best characteristics as a possible fluorescent probe for dsDNA and can serve as a sensitive and selective probe for dsDNA in the presence of HSA. Photochemical properties of MCD complexed with DNA have been also studied. An increase in the quantum yield of the triplet states of MCD in complexes with DNA has been found, which may be important for using these dyes as potential candidates in photodynamic therapy.

Broadband EPR Spectroscopy of the Triplet State: Multi-Frequency Analysis of Copper Acetate Monohydrate.

Electron paramagnetic resonance spectroscopy is a long-standing method for the exploration of electronic structures of transition ion complexes. The difficulty of its analysis varies considerably, not only with the nature of the spin system, but more so with the relative magnitudes of the magnetic interactions to which the spin is subject, where particularly challenging cases ensue when two interactions are of comparable magnitude. A case in point is the triplet system S = 1 of coordination complexes with two unpaired electrons when the electronic Zeeman interaction and the electronic zero-field interaction are similar in strength. This situation occurs in the X-band spectra of the thermally excited triplet state of dinuclear copper(II) complexes, exemplified by copper acetate monohydrate. In this study, applicability of the recently developed low-frequency broadband EPR spectrometer to S = 1 systems is investigated on the analysis of multi-frequency, 0.5-16 GHz, data from [Cu(CH3COO)2H2O]2. Global fitting affords the spin Hamiltonian parameters gz = 2.365 ± 0.008; gy = 2.055 ± 0.010; gx = 2.077 ± 0.005; Az = 64 gauss; D = 0.335 ± 0.002 cm-1; E = 0.0105 ± 0.0003 cm-1. The latter two define zero-field absorptions at ca. 630, 7730, and 10,360 MHz, which show up in the spectra as one half of a sharpened symmetrical line. Overall, the EPR line shape is Lorentzian, reflecting spin-lattice relaxation, which is a combination of an unusual, essentially temperature-independent, inverted Orbach process via the S = 0 ground state, and a Raman process proportional to T2. Other broadening mechanisms are limited to at best minor contributions from a distribution in E values, and from dipolar interaction with neighboring copper pairs. Monitoring of a first-order double-quantum transition between 8 and 35 GHz shows a previously unnoticed very complex line shape behavior, which should be the subject of future research.

Heavy Atom-Free Triplet Photosensitizers: Molecular Structure Design, Photophysical Properties and Application in Photodynamic Therapy.

Photodynamic therapy (PDT) is a promising method for the treatment of cancer, because of its advantages including a low toxicity, non-drug-resistant character, and targeting capability. From a photochemical aspect, a critical property of triplet photosensitizers (PSs) used for PDT reagents is the intersystem crossing (ISC) efficiency. Conventional PDT reagents are limited to porphyrin compounds. However, these compounds are difficult to prepare, purify, and derivatize. Thus, new molecular structure paradigms are desired to develop novel, efficient, and versatile PDT reagents, especially those contain no heavy atoms, such as Pt or I, etc. Unfortunately, the ISC ability of heavy atom-free organic compounds is usually elusive, and it is difficult to predict the ISC capability of these compounds and design novel heavy atom-free PDT reagents. Herein, from a photophysical perspective, we summarize the recent developments of heavy atom-free triplet PSs, including methods based on radical-enhanced ISC (REISC, facilitated by electron spin-spin interaction), twisted π-conjugation system-induced ISC, the use of fullerene C60 as an electron spin converter in antenna-C60 dyads, energetically matched S1/Tn states-enhanced ISC, etc. The application of these compounds in PDT is also briefly introduced. Most of the presented examples are the works of our research group.

Highly Twisted Conformation Thiopyrylium Photosensitizers for In Vivo Near Infrared-II Imaging and Rapid Inactivation of Coronavirus.

Despite significant effort, a majority of heavy-atom-free photosensitizers have short excitation wavelengths, thereby hampering their biomedical applications. Here, we present a facile approach for developing efficient near-infrared (NIR) heavy-atom-free photosensitizers. Based on a series of thiopyrylium-based NIR-II (1000-1700 nm) dyads, we found that the star dyad HD with a sterically bulky and electron-rich moiety exhibited configuration torsion and significantly enhanced intersystem crossing (ISC) compared to the parent dyad. The electron excitation characteristics of HD changed from local excitation (LE) to charge transfer (CT)-domain, contributing to a ≈6-fold reduction in energy gap (ΔEST ), a ≈10-fold accelerated ISC process, and a ≈31.49-fold elevated reactive oxygen species (ROS) quantum yield. The optimized SP@HD-PEG2K lung-targeting dots enabled real-time NIR-II lung imaging, which precisely guided rapid pulmonary coronavirus inactivation.

Functional Roles of Polymers in Room-Temperature Phosphorescent Materials: Modulation of Intersystem Crossing, Air Sensitivity and Biological Activity.

Organic room-temperature phosphorescent (RTP) materials routinely incorporate polymeric components, which usually act as non-functional or "inert" media to protect excited-state phosphors from thermal and collisional quenching, but are lesser explored for other influences. Here, we report some exemplary "active roles" of polymer matrices played in organic RTP materials, including: 1) color modulation of total delayed emissions via balancing the population ratio between thermally-activated delayed fluorescence (TADF) and RTP due to dielectric-dependent intersystem crossing; 2) altered air sensitivity of RTP materials by generating various surface morphologies such as nano-sized granules; 3) enhanced bacterial elimination for enhanced electrostatic interactions with negatively charged bio-membranes. These active roles demonstrated that the vast library of polymeric structures and functionalities can be married to organic phosphors to broaden new application horizons for RTP materials.

Thermally Activated Long Persistent Luminescence of Organic Inorganic Metal Halides.

Long persistent luminescence (LPL) materials of SrAl2 O4 doped with Eu2+ or Dy3+ can maintain emission over hours after ceasing the excitation but suffer from insolubility, high cost, and harsh preparation. Recently, organic LPL of guest-host exciplex systems has been demonstrated via an intermediate charge-separated state with flexible design but poor air-stability. Here, we synthesized a nontoxic two-dimensional organic-inorganic metal hybrid halides (OIMHs), called PBA2 [ZnX4 ] with X=Br or Cl and PBA=4-phenylbenzylamine. These materials exhibit stable LPL emission over minutes at room-temperature, which is two orders of magnitude longer than those of previously reported OIMHs. The mechanism study shows that the LPL emission comes from thermally activated charge separation state rather than room-temperature phosphorescence. Moreover, the LPL of PBA2 [ZnX4 ] can be excited by low power sources, representing an effective strategy for developing low-cost and high-stability LPL systems.

Modulating Triplet Excited States of Organic Semiconductors via Tuning Molecular Conformation for Dual-ratiometric Thermometers.

The dual-ratiometric thermometry is one of highly accurate methods for microscopic thermal measurement in biological systems. Herein, a series of chromone derivatives with noncovalently intramolecular interactions (NIIs) were designed and synthesized for ratiometric thermometers. The triplet states of these organic compounds were systematically tuned upon regulating the conformation with NIIs to yield efficient room temperature phosphorescence and large wavelength difference between fluorescence and phosphorescence simultaneously. As a result, an unprecedent organic 3D dual-ratiometric thermometer was established based on the intensity ratio and lifetime ratio of fluorescence/phosphorescence vs temperature, which was used for in vitro and in vivo bio-thermometry with high accuracy. This work provides a novel method to achieve organic dual ratiometric thermometers via tuning the triplet excited states.

Disorder-Enhanced Charge-Transfer-Mediated Room-Temperature Phosphorescence in Polymer Media.

Room-temperature phosphorescence (RTP) polymers have important applications for biological imaging, oxygen sensing, data encryption, and photodynamic therapy. Despite the many advantages polymeric materials offer such as great control over gas permeability and processing flexibility, disorder is traditionally considered as an intrinsic negative impact on the efficiency for embedded RTP luminophores, as various allowed thermal motions could quench the emitting states. However, we propose that such disorder-enabled freedoms of microscopic motions can be beneficial for charge-transfer-mediated RTP, which is facilitated by molecular conformational changes among different electronic transition states. Using the "classic" pyrene-aniline exciplex as an example, we demonstrate the mutual enhancement of red/near-infrared and green RTP emissions from the pyrene and aniline moieties, respectively, upon doping the aniline polymer with trace pyrene derivatives. In comparison, a pyrene-doped crystal formed with the same aniline structure exhibits only charge-transfer fluorescence with no red or green RTP observed, suggesting that order suppresses the RTP channels. The proposed polymerization strategy may be used as a unified method to generate multi-emissive polymeric RTP materials from a vast pool of known and unknown exciplexes and charge-transfer complexes.