The phenoxyl radical and two of its isotopomers were investigated by UV-VIS IR polarization spectroscopy molecular samples immobilized in cryogenic argon matrices. Analysis the combined electronic infrared linear dichroism data led to determination absolute transition moment directions symmetry assignments for four low-lying excited states. bands observed at 16 000, 25 200, 33 900, 41 800 cm−1 assigned A12, B12, B12 π–π* states, respectively. A very weak near-infrared close 8900 was an...

Comparison of photostability in degassed and aerated toluene solutions is reported for 5,10,15,20-tetraphenylporphyrin, 5,10,15-tri(p-tolyl)porphyrin, their zinc analogues. After degassing, quantum yields photodegradation are higher, but the photodecomposition rates decrease. Lower stability deoxygenated due to much longer triplet lifetimes: 200-300 microseconds, compared 200-360 ns non-degassed toluene. For porphyrins, LC-MS results show that initial photoproduct contains two oxygen atoms....

Phenoxyl radical (C6H5O) was prepared photochemically in low-temperature argon matrices. The infrared absorption spectra were obtained for C6H5O and the isotopically labeled species C6D5O 1-13C12C5H5O. All but one IR-active fundamental vibrations detected, most of them not previously observed. Combination results from IR linear dichroism measurements on photooriented samples, determination absolute intensities with help internal standards, analysis isotopic shifts, quantum chemical...

Single molecule surface-enhanced resonance Raman scattering (SERRS) spectra have been obtained for the parent porphycene (Pc-d0) and its deuterated isotopologue (Pc-d12), located on gold silver nanoparticles. Equal populations of "hot spots" by two isotopologues are observed 1 : mixtures in a higher concentration range single regime (5 × 10(-9) M). For decreasing concentrations, hot spots preferentially populated undeuterated molecules. This is interpreted as an indication lower surface...

The optical and electrochemical properties are compared for aza-BODIPY dyes that differ by virtue of the substituents at 1,7- 3,5-positions backbone.

The first-in-class luminescent dinucleoside phosphate analogs with a [Re2(μ-Cl)2(CO)6(μ-pyridazine)] "click" linker as replacement for the natural group are reported together synthesis of adenosine and thymidine derivatives having entity attached to positions 5' 3', respectively. These compounds were synthesized by applying inverse-electron-demand Diels-Alder copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition reactions in three or four steps. obtained exhibited orange emission (λPL ≈...

Three recently obtained expanded porphyrins represent nice examples of compounds for which the electronic and spectral properties can be predicted from symmetry considerations alone. Perimeter-model-based theoretical analysis structure doubly protonated cyclo[6], cyclo[7], cyclo[8]pyrrole leads to anticipation qualitatively same absorption magnetic circular dichroism patterns all three compounds. These predictions are fully confirmed by experiments, as well DFT INDO/S calculations. Due a...

The analysis of spectral-kinetic results transient absorption and phosphorescence experiments has been carried out in a wide temperature range (80–293 K) for series Pd-octaethylporphyrin derivatives (PdOEP) with increasing number bulky meso-phenyl substituents. In order to elucidate the influence steric hindrance interactions, as well porphyrin macrocycle non-planarity on photophysical characteristics relaxation pathways triplet states, following parameters were compared: i) T-state...

Functionalized β-ketoenoles for efficient fluorescence sensing of protein amyloid fibrils giving strong emission increase up to 0.5 QY are designed.

Dual emissive dinuclear Pt(<sc>ii</sc>) complexes showing green fluorescence and infrared phosphorescence stemming from a single chromophoric moiety are reported. The compounds efficient O₂ photosensitizers with ¹O₂ generation efficiencies of up to 77%.

Abstract Normal and heavy water are solvents most commonly used to study the isotope effect. The effect of a solvent significantly influences behavior single molecule in solution, especially when there interactions between solute. influence becomes more significant D 2 O/H O since hydrogen bond H is slightly weaker than its counterpart (deuterium bond) O. Herein, we characterize mixture normal on solvation HOD molecule. We show that affects proximal molecules, these disturbances much water....

Abstract Free base and zinc porphyrins functionalized with cyclooctatetraene (COT), a molecule known as good triplet‐state quencher, have been obtained characterized in detail by structural, spectral, photophysical techniques. Substitution COT leads to dramatic decrease of the intrinsic lifetime porphyrin triplet. As result, photostability oxygen‐free solution increases two three orders magnitude. In non‐degassed solutions, improvement is about tenfold for porphyrins, but free bases become...

Electronic absorption and magnetic circular dichroism (MCD) spectra of 2,3,6,7,11,12,17,18-octaethylcorrphycene, a constitutional isomer porphyrin, were recorded for the neutral, doubly protonated, deprotonated forms. The closely resemble those parent porphyrin are quite different from other isomers such as porphycene hemiporphycene. Theoretical considerations based on Michl's perimeter model allow one to understand spectral properties observed within series composed porphycene,...

Reliable assignment of 55 out 57 vibrational modes has been achieved for 1H-pyrrolo[3,2-h]quinoline using IR, Raman, and fluorescence spectroscopy combined with quantum chemical calculations. The experiments provided a data set assessing the performance different models/basis sets predicting frequencies, as well IR Raman intensities molecule 13 heavy atoms. Among six tested DFT functionals, hybrid B3LYP used Pople's split-valence basis is suggested best choice accurate cost-effective...

Molecules that can simultaneously act as hydrogen bond donors and acceptors often exhibit completely different photophysical behavior in protic aprotic solvents. Formation of multiple bonds with, for example, water or alcohols, may lead to enhanced internal conversion; a result, triplet formation efficiency be reduced. These changes characteristics influence the photostability. In order check this hypothesis, we have investigated spectroscopy, photophysics, photostability caused by...

The photophysics and photostability of 12,13-dihydro-5H-indolo[3,2-c]acridine (IA), a rigid bifunctional indole derivative with proton donor/acceptor functionalities, can be drastically changed by the environment. formation hydrogen bonds alcohols leads to significant decrease triplet efficiency an increase photostability. photodegradation yield was found about two hundred times lower in methanol 1-propanol than n-hexane or acetonitrile. A similar effect has been reported for...

Photochromism of monothiodibenzoylmethane has been studied in a number environments at different temperatures. Direct laser irradiation sample located the NMR magnet allowed situ monitoring phototransformation products, determining their structure, and measuring kinetics back reaction. These observations, along with data obtained using electronic vibrational spectroscopies for rare gas matrix-isolated samples, glasses, polymers, solutions, as well results quantum-chemical calculations,...

New Pd(II) and Pt(II) complexes with a highly electron-deficient ligand (H2 PcF64 ) were conveniently prepared in three-step synthesis. This is the first time that phosphorescence of phthalocyanines H2 framework has been measured. Based on these measurements, triplet-state energies (ET directly determined. Transient absorption experiments revealed broad T1 →Tn spanning from ca. 350 to 1000 nm allowed determination lifetimes. Removal Pd or Pt perfluoro-phthalocyanine resulted significant...

Abstract Thioacetylacetone and its variously deuterated isotopomers have been investigated using electronic vibrational spectroscopy combined with quantum chemical calculations. is known for photochromic properties, but the structures of initial final forms subject a long debate. Analysis IR spectra recorded in low‐temperature argon xenon matrices, room‐temperature solutions, gas phase has allowed us to establish nature species precursor. Similar case another β ‐thioxoketone,...

Abstract Amyloid fibrils are rigid β‐pleated protein aggregates that connected with series of harmful diseases and at the same time promising as base for novel nanomaterials. Thus, design compounds able to inhibit or redirect those formation is important both biomedical aims nanotechnology applications. Here, we studied effect tetraphenylporphyrins (metal free, their Cu Pd complexes, functionalized by carboxy amino groups on periphery) insulin amyloid self‐assembling. The strongest impact...

Mono- and dinuclear Pt( ii ) complexes of a new ditopic ligand with thiophene cyclometalating core are reported. The mononuclear complex shows dual emission fluorescence phosphorescence is demonstrated as channel bioimaging probe.