The ground and excited state photophysical properties of a series fac-[Re(L)(CO)3(α-diimine)]n+ complexes, where L = Br–, Cl–, 4-dimethylaminopyridine (dmap) pyridine (py) have been extensively studied utilizing numerous electronic vibrational spectroscopic techniques in conjunction with suite quantum chemical methods. α-diimine ligand consists 1,10-phenanthroline the highly electron donating triphenylamine (TPA) appended 5 position. This gives rise to intraligand charge transfer (ILCT)...

The synthesis, optical characterization and computational modeling of seven benzo[c][1,2,5]thiadiazole (BTD) donor-acceptor dyes are reported. These have been studied using electrochemical analysis, electronic absorption, emission, Raman resonance spectroscopies coupled with various density functional theoretical approaches. Crystal structure geometries on a number these compounds also spectra dominated by low energy charge-transfer states; this may be modulated the coupling between donor...

Supramolecular photocatalysts consisting of photosensitizer (PS), bridging ligand (BL), and catalytic center (CAT) have garnered significant attention in solar fuel applications. In this study, the photophysics photocatalytic properties two Ru(II)-based dinuclear complexes, specifically [(tbbpy)2Ru(p(Ph)np)Rh(Cp*)Cl]3+ (n = 0, 1; Ru(pp)Rh for n 0 or Ru(p(Ph)p)Rh tbbpy 4,4'-di-tert-butyl-2,2'-bipyridine, Cp* pentamethylcyclopentadienyl, Ph phenyl, p 1,10-phenanthroline), are investigated....

A series of donor-acceptor compounds is reported in which the energy triarylamine donor systematically tuned through para substitution with electron-donating methoxy and electron-withdrawing cyano groups. The acceptor units investigated are benzothiadiazole (btd), dipyridophenazine (dppz), its [ReCl(CO)3(dppz)] complex. effect modulating on electronic photophysical properties using (1)H NMR spectroscopy, DFT calculations, electrochemistry, absorption emission spectroscopies, ground state...

A series of Ru(II) 2,2′-bipyridine (bpy) complexes with an electron-accepting dipyrido[3,2-a:2′,3′-c]phenazine (dppz) ligand coupled to electron-donating triarylamine (TAA) group have been investigated. Systematic alteration a bridging unit between the dppz and TAA allowed exploration into how communication donor acceptor is perturbed by distance, as well steric electronic effects. The effect on properties systems was characterized using variety spectroscopic methods, including Fourier...

Excited states are the key species in photocatalysis, while critical parameters that govern their applications (i) excitation energy, (ii) accessibility, and (iii) lifetime. However, molecular transition metal-based photosensitizers, there is a design tension between creation of long-lived excited (triplet), e.g., metal-to-ligand charge transfer (3MLCT) population such states. Long-lived triplet have low spin-orbit coupling (SOC) hence low. Thus, state can be populated but inefficiently. If...

Abstract Quantum chemical methods have been utilised to explore the kinetics and thermodynamics of a prominent charge recombination pathway in series Ru II based molecular photocatalysts. Selective tuning coordination sphere, replacing tbbpy ligands hydrogen evolving parent photocatalyst with electron rich, biimidazole ligands, promotes unidirectional transfer towards bridging ligand during initial photoexcitation. These electronic effects are also significant triplet manifold, where...

The photophysical properties of a series rhenium(I) tricarbonyl and platinum(II) bis(acetylide) complexes containing triphenylamine (TPA)-substituted 1,10-phenanthroline ligand have been examined. possess both metal-to-ligand charge-transfer (MLCT) intraligand (ILCT) transitions that absorb in the visible region. relative energies ordering absorbing CT states successfully controlled by changing metal center modulating donating ability TPA group through addition electron-donating methoxy...

A series of photosensitizers comprised both an inorganic and organic chromophore are investigated in a joint synthetic, spectroscopic, theoretical study. This bichromophoric design strategy provides means by which to significantly increase the excited state lifetime isolating away from metal center following intersystem crossing. variable bridging group is incorporated between donor acceptor units chromophore, its influence on properties explored. The Franck–Condon (FC) photophysics...

The synthesis, spectroscopic characterization, and computational modeling of seven benzo[ c][2,1,3]thiadiazole-based donor-acceptor dyes is reported. Using a range linker units, it possible to alter the lowest energy transition in terms intensity (from 8000 25000 L mol-1 cm-1) wavelength 350 430 nm). Resonance Raman spectroscopy was used concert with DFT calculations indicate that unit participates charge transfer processes. In each compound excited state behavior appears be primarily...

A series of electron donor–acceptor compounds are reported in which both the donor and acceptor strengths systematically altered using mono-, bi-, terthiophene as donors benzo[c][1,2,5]thiadiazole (btd), dipyrido[3,2-a:2′,3′-c]phenazine (dppz), corresponding rhenium(I) complex, [ReCl(CO)3(dppz)], acceptors. The electronic properties characterized electrochemistry, absorbance emission spectroscopies, transient absorption spectroscopy. effect on frontier molecular orbital localization...

The ground- and excited-state properties of a series [ReCl(CO)3(dppz)] complexes with substituted donor groups were investigated. Alteration donor-acceptor communication through modulation torsional angle the number nature substituents allowed effects on photophysical to be characterized though both computational spectroscopic techniques, including time-dependent density functional theory resonance Raman time-resolved infrared spectroscopy. ground-state optical show significant variation as...

A transition-metal-based donor-(linker)-acceptor system can produce long-lived charge transfer excited states using visible excitation wavelengths. The ground- and excited-state photophysical properties of a series [ReCl(CO)3(dppz-(linker)-TPA)] complexes, with varying donor acceptor energies, have been systematically studied spectroscopic techniques (both vibrational electronic) supported by computational chemistry. state is 3ILCT in nature for all complexes studied, characterized through...

The photophysical properties of a series heteroleptic Ru(II) complexes the form [Ru(phen)2(phen-5,6-R2)]2+, where phen = 1,10-phenanthroline and R phenyl (Ph), p-tert-butylbenzene (p-Ph-tBu), p-methoxybenzene (p-Ph-OMe), 2-naphthalene (2-naph), have been measured. Variation group does not greatly perturb electronic ground state, which were explored with absorption resonance Raman spectroscopy are akin to those archetypal parent complex [Ru(phen)3]2+. All shown possess emissive 3MLCT states,...

In this study, we present two ruthenium(ii) diimine complexes appended with ferrocene which show metal to ligand charge transfer 3MLCT emission lifetimes around 630 ns. We also a similar complex units has decreased emission. These have been studied by electrochemical, electronic absorption, and Raman, resonance Raman transient means, coupled density functional theoretical approaches. For these systems, the optical spectra are dominated low energy MLCT transition; can be modulated presence of...

Rhenium tetrazolato complexes appended to phenol substituents are exploited for cell labelling.

The ability to identify the contents of a sealed container, without need extract sample, is desirable in applications ranging from forensics product quality control. One technique suited this inverse spatially offset Raman spectroscopy (ISORS) which illuminates sample interest with an annular beam light and collects scattering center ring, thereby retrieving chemical signature while suppressing signal container. Here we explore detail relative benefits recently developed variant ISORS,...

[M(ppy)(big)] (M = Pt(<sc>ii</sc>), Pd(<sc>ii</sc>), big 1,5-diarylbiguanide) complexes are synthesised and their promise as tectons for hydrogen bond-directed assembly is explored.

Abstract Bridged photosensitizer‐catalyst systems are promising models to study photocatalytic hydrogen evolution. However, the in literature structurally diverse and therefore hard compare. Many show highly complex photophysics including several accepting orbitals for excited state, as a result catalytic activity is predict. Here we present bimetallic Ru−Pt photocatalyst bearing peripheral spectator ligands at ruthenium(II) photocenter member of Ru‐tpphz‐Pt family. Consequently, it features...

Compared with triplet metal-to-ligand charge transfer (3MLCT) states, charge-separated (3CS) excited states involving organic moieties, such as intra-ligand or ligand-to-ligand (3ILCT and 3LLCT) tend to possess longer-lived due the weak spin-orbit coupling closed-shell ground state (GS). Thus, combination of both inorganic chromophores enables isolation onto chromophore. Herein, we aim elucidate entangled excited-state relaxation processes in a Ru(II)-terpyridyl push-pull triad (RuCl) joint...