UV-vis Electronic Absorption Research Articles

Copper(II) complexes of acylhydrazones: synthesis, characterization and DNA interaction

Two new acylhydrazone copper(II) complexes of 4‐hydroxy‐N′‐[(1E)‐1‐(4‐methylphenyl)ethylidene]benzohydrazide (HL1) and 4 ethyl [4‐({(2E)‐2‐[1‐(4‐methylphenyl)ethylidene]hydrazinyl}carbonyl)phenoxy]acetate (HL2) have been synthesized and characterized. The structures of both acylhydrazone and copper(II) complexes were identified by elemental analysis, infrared spectra, UV–visible electronic absorption spectra, magnetic susceptibility measurements, TGA and powder X‐ray diffraction. DNA binding and DNA cleavage activities of the synthesized copper complexes were examined by using UV‐visible titration and agarose gel electrophoresis, respectively. The effect of complex concentration on the DNA cleavage reactions in the absence and presence of H2O2 was also investigated. The results indicate that all the complexes bind slightly to calf thymus DNA and cleavage pBR322 DNA. The mechanistic studies demonstrate that a hydrogen peroxide‐derived species and singlet oxygen (1O2) are the active oxidative species for DNA cleavage. Copyright © 2013 John Wiley & Sons, Ltd.

The parent tetrathiafulvalene–terpyridine dyad: synthesis and metal binding properties

The still unknown parent tetrathiafulvalene–terpyridine- ligand 5 (namely TTF–terpy), was synthesized through a straightforward strategy. The dyad exhibits an intramolecular charge transfer (ICT) which was evidenced by UV–vis electronic absorption. Complexation of various transition metal cations by this redox-active ligand was studied by UV–vis absorption spectroscopy as well as by cyclic voltammetry titration studies, supporting the dual functional character of this system. In addition, these results demonstrate that ligand 5 is a suitable building block for the preparation of electroactive neutral as well as charged metal complexes.

Synthesis, characterization and DNA interaction of new copper(II) complexes of Schiff base-aroylhydrazones bearing naphthalene ring

Two new copper(II) complexes with the condensation products of methyl 2-naphthyl ketone with 4-hydroxybenzohydrazide, 4-hydroxy-N′-[(1Z)-1-(naphthalen-2-yl)ethylidene]benzohydrazide [HL1] and (Z)-ethyl 2-(4-(2-(1-(naphthalen-2-yl)ethylidene)hydrazinecarbonyl)phenoxy)acetate (HL2) were synthesized and characterized by elemental analysis, infrared spectra, UV–Vis electronic absorption spectra, magnetic susceptibility measurements, TGA, powder XRD and SEM–EDS. The binding properties of the copper(II) complexes with calf thymus DNA were studied by using the absorption titration method. DNA cleavage activities of the synthesized copper complexes were examined by using agarose gel electrophoresis. The effect of complex concentration on the DNA cleavage reactions in the absence and presence of H2O2 was also investigated. The experimental results suggest that the copper complexes bind significantly to calf thymus DNA by both groove binding and intercalation modes and cleavage effectively pBR322 DNA. The mechanistic studies demonstrate that a hydrogen peroxide-derived species and singlet oxygen (1O2) are the active oxidative species for DNA cleavage.

Real-time Monitoring of Ligand-receptor Interactions with Fluorescence Resonance Energy Transfer

FRET is a process whereby energy is non-radiatively transferred from an excited donor molecule to a ground-state acceptor molecule through long-range dipole-dipole interactions1. In the present sensing assay, we utilize an interesting property of PDA: blue-shift in the UV-Vis electronic absorption spectrum of PDA (Figure 1) after an analyte interacts with receptors attached to PDA2,3,4,7. This shift in the PDA absorption spectrum provides changes in the spectral overlap (J) between PDA (acceptor) and rhodamine (donor) that leads to changes in the FRET efficiency. Thus, the interactions between analyte (ligand) and receptors are detected through FRET between donor fluorophores and PDA. In particular, we show the sensing of a model protein molecule streptavidin. We also demonstrate the covalent-binding of bovine serum albumin (BSA) to the liposome surface with FRET mechanism. These interactions between the bilayer liposomes and protein molecules can be sensed in real-time. The proposed method is a general method for sensing small chemical and large biochemical molecules. Since fluorescence is intrinsically more sensitive than colorimetry, the detection limit of the assay can be in sub-nanomolar range or lower8. Further, PDA can act as a universal acceptor in FRET, which means that multiple sensors can be developed with PDA (acceptor) functionalized with donors and different receptors attached on the surface of PDA liposomes.

Real-time Monitoring of Ligand-receptor Interactions with Fluorescence Resonance Energy Transfer

FRET is a process whereby energy is non-radiatively transferred from an excited donor molecule to a ground-state acceptor molecule through long-range dipole-dipole interactions. In the present sensing assay, we utilize an interesting property of PDA: blue-shift in the UV-Vis electronic absorption spectrum of PDA (Figure 1) after an analyte interacts with receptors attached to PDA. This shift in the PDA absorption spectrum provides changes in the spectral overlap (J) between PDA (acceptor) and rhodamine (donor) that leads to changes in the FRET efficiency. Thus, the interactions between analyte (ligand) and receptors are detected through FRET between donor fluorophores and PDA. In particular, we show the sensing of a model protein molecule streptavidin. We also demonstrate the covalent-binding of bovine serum albumin (BSA) to the liposome surface with FRET mechanism. These interactions between the bilayer liposomes and protein molecules can be sensed in real-time. The proposed method is a general method for sensing small chemical and large biochemical molecules. Since fluorescence is intrinsically more sensitive than colorimetry, the detection limit of the assay can be in sub-nanomolar range or lower. Further, PDA can act as a universal acceptor in FRET, which means that multiple sensors can be developed with PDA (acceptor) functionalized with donors and different receptors attached on the surface of PDA liposomes.

Evaluation of the doping process of polyaniline produced inside the mesopores of a sulfonic acid grafted MCM-41

The use of mesoporous materials as hosts for polymers production in a confined environment is a field of great interest, especially in the case of conducting polymers. This method provides size and morphological control in nanoscopic scale and permits the formation of polymeric chains with good linearity and fewer defects, characteristics that could promote enhanced electrical conductivity.In this study it was evaluated some aspects of the polymerization of aniline inside the pores of the MCM-41 silica post-modified with sulfonic acid groups (–SO3H) covalently bonded to the surfaces. The produced hybrid material containing polyaniline (PAni) into the pores was characterized by X-ray diffractometry, thermogravimetric analysis, UV–Vis electronic absorption, Fourier transformed infrared spectroscopies and scanning and transmission electron microscopies.The results indicate that PAni was successfully generated inside the pores of the sulfonic acid grafted MCM-41 and that the acid group was capable of protonating the polymer, producing PAni in the emeraldine salt state, the most conductive one, without the addition of another acid source during the polymerization step. The grafted sulfonic acid groups also promoted a stronger interaction between inorganic matrix and aniline than the observed in non-functionalized MCM-41, which resulted in less monomer and polymer lixiviation during the polymerization step.

Synthesis, characterization, crystal structure and theoretical approach of Cu(II) complex with 4-{(Z)-[(2-hydroxybenzoyl)hydrazono]methyl}benzoic acid

Abstract The metal complex of [CuL2]·2DMF (L = 4-{(Z)-[(2-hydroxybenzoyl)hydrazono]methyl}benzoic acid, DMF = N,N-dimethylformamide) (1) had been synthesized and characterized by spectral method(IR), UV–Vis electronic absorption spectra, fluorescence spectra, elemental analysis, electrochemistry, thermal analysis (TG, DTG) and single crystal X-ray diffraction techniques. In the complex, the ligands act as univalent anion bidentate and coordination takes place in the enol tautomeric form with the enolic oxygen and azomethine nitrogen atoms. Molecular geometry from X-ray experiment of the title compound in the ground-state has been compared using the density functional method (B3LYP) and LANL2DZ basis set. DFT calculations at B3LYP/LANL2DZ level of theory prove that the electronic spectra of CuL2·2DMF is attributed to intra-complex electronic transitions as well as π–π* electronic transitions. Also, Mulliken charge analysis, natural bond orbitals (NBO), Wiberg bond index and frontier molecular orbitals (FMO) were performed at B3LYP/LANL2DZ level of theory. In addition, complex 1 exhibits strong photoluminescent emission at room temperature. The electrochemical studies reveal that redox of Cu2+/Cu+ in the complex are quasi-reversible processes. The result of TG analysis shows that the title complex was stable under 100.0 °C.

ASYMMETRIC BIS(BIDENTATE) AZINE LIGAND AND TRANSITION METAL COMPLEXES: SYNTHESIS, CHARACTERIZATION, DNA-BINDING AND CLEAVAGE STUDIES AND EXTRACTION PROPERTIES FOR SELECTED METALS AND DICHROMATE ANIONS

New bis(bidentate) azine NNN’N’ donor ligand was prepared by linking (1Z,1’Z)-1,1’-{propane-1,3-diylbis[oxybenzene-4,1-diyl(1Z)eth-1-yl-1-ylidene]} dihydra-zine to pyridine-2-carbaldehyde. Two kinds of copper(II) and nickel(II) complexes with different stoichiometries were prepared. Reaction of bis(azine) ligand with Cu(II) and Ni(II) chloride with 1:1 molar ratio gave azine complexes with stoichiometry [M(L)Cl 2 ] while 2:1 molar ratio reaction of Cu(II) and Ni(II) chloride with bis(azine) composed binuclear copper complexes with general stoichiometry [M 2 (L)Cl 4 ]. The structures of both bis-azine ligand and its complexes were identified by elemental analysis, infrared spectra, UV–Vis electronic absorption spectra and magnetic susceptibility measurements, TGA and powder XRD. DNA binding and DNA cleavage activities of the synthesized metal complexes were examined by using UV-vis titration and agarose gel electrophoresis, respectively. The results indicate that all the complexes bind significantly calf thymus DNA and cleavage pBR322 DNA. Furthermore, the complexing properties of the bis-azine ligand toward selected transition metal cations and dichromate anions were also reported.

Synthesis and characterization of bis-acylhydrazone derivatives as tetradentate ligands and their dinuclear metal(II) complexes

Two novel bis-acylhydrazone where as 1,4-diacetylbenzene bis(4-hydroxy benzoyl hydrazone) H_2L^1 and 1,4-diacetylbenzene bis(4-nitrobenzoyl hydrazone) H_2L^2 ligands bearing two hydrazone side groups and their metal(II) complexes have been synthesized and characterized by ^1H-NMR^ 13 C-NMR, elemental analysis, FT-IR infrared spectra, magnetic susceptibility measurements and UV-vis electronic absorption spectra. The L_1H_2, L_2H_2) ligands were synthesized by reacting 4-hydroxybenzohydrazide and 4-nitrobenzohydrazide with 1,4-diacetylbenzene, respectively. The ligands H_2L^1, L_2H_2) react with metal(II) chlorides anhydrous to form polymeric dinuclear metal(II) complexes with general formula [(M_2(L_x)_2_n] with a metal to ligand ratio of 1:1 when [x = 1, 2; M = Ni(II), Co(II), Cu(II), Zn(II) and Cd(II)]. In the complexes, the ligands act as dianionic tetradentate and coordination takes place in the enol tautomeric form with the enolic oxygen and azomethine nitrogen atoms while the phenolic hydroxyl and nitro groups of dihyrazone moiety do not participate in coordination.

Novel homogeneous catalyst comprising ruthenium and trimethylphosphite for the hydrolysis of sodium borohydride

Homogeneous catalytic hydrolysis of sodium borohydride starting with Ru(acac) 3 (acac = acetylacetonate) and P(OMe) 3 was followed by monitoring the hydrogen evolution and the UV–vis electronic absorption spectra which shows the conversion of all ruthenium(III) to a ruthenium(II) species, most likely acting as catalyst. This active catalyst is alive only under reducing conditions and converted mainly to Ru(acac) 3 along with other minor complexes when the catalytic reaction is over. A ruthenium(II) complex was isolated from the reaction solution after the complete catalytic hydrolysis of sodium borohydride and characterized to be [Ru{P(OMe) 3} 4H 2] by single crystal XRD, MS, UV–vis, FTIR, 1H, 13C and 31P NMR spectroscopy. [Ru{P(OMe) 3} 4H 2] complex crystallizes in the triclinic space group P-1 with a = 10.066(2) Å, b = 19.108(3) Å, c = 20.938(4) Å, α = 78.839(14)°, β = 87.308(16)° and γ = 79.506(14)°. This ruthenium(II) complex was found not to be the active catalyst in the hydrolysis of sodium borohydride, rather one of its conversion products after catalysis. Although the active catalyst could not be isolated from the reaction solution, it could be stabilized by adding chelating 2,2′-bipyridine into the solution during the catalysis. Thus, a stabilized form of the active catalyst, [Ru(acac)(bipy){P(OMe) 3}H], could be isolated and characterized by MS, UV–vis, FTIR, 1H, 13C and 31P NMR spectroscopy. [Ru(acac)(bipy){P(OMe) 3}H] is expectedly not as active as the ruthenium(II) species formed in situ during the catalysis. Taking all the results together reveals that the active catalyst is a ruthenium(II) complex, either [Ru(acac){P(OMe) 3} 3H] or most likely its dissociation product, [Ru(acac){P(OMe) 3} 2H]. Control experiments showed that 2,2′-bipyridine can replace only the trimethylphosphite ligands but not the acetylacetonato ligand in the ruthenium(II) complex.

The syntheses and characterization of Os(II) and Ru(II)/Os(II) bimetallic complexes with dipyrido(2,3-a:3′,2′-j)phenazine (dpop′) and the bridging ligand 2,3,5,6-tetra(2-pyridyl)-pyrazine (tppz)

The syntheses of mixed ligand mono metallic [Os(dpop′)(tppz)](PF6)2, homo-bimetallic [(dpop′)Os(tppz)Os(dpop′)](PF6)4 and mixed metal bimetallic [(dpop′)Ru(tppz)Os(dpop′)](PF6)4 (dpop′=dipyrido(2,3-a:3′,2′-j)phenazine; tppz=2,3,5,6-tetra(2-pyridyl)-pyrazine) complexes is described. NMR spectroscopy was used to confirm pure products were separated from similar species. The 1H NMR spectrum for the mixed metal Ru/Os bimetallic complex ion reflects additive components of the Ru/Ru and Os/Os bimetallic species. Proton resonances on Ru(II) bonded ligands are upfield from Os(II) bonded ligands. Cyclic voltammetry for the Os/Os and Ru/Os bimetallic complex ions show the reversible tppz0/−1 reduction at less negative potential than the dpop′0/−1 reduction. Additionally, the [(dpop′)Os(tppz)Os(dpop′)]4+ ion displays reductive coupling of the remote terminal dpop′ ligands that is not observed in the bimetallic Ru/Ru species, indicating larger metal–ligand mixing occurs for Os(II) than Ru(II) complexes. The UV–Vis electronic absorption spectra for all complex ions show intense Os(dπ)→dpop′(π∗) and Os(dπ)→tppz(π∗) MLCT transitions in the visible spectrum with IL transitions in the UV.

Electronic spectra and photophysics of the α-carboline (1-azacarbazole) monomer

The UV–vis electronic absorption and emission spectra of α-carboline or 1-azacarbazole, 9H-pyrido[2,3- b]indole, AC, have been investigated in aprotic solvents. Radiative, k r, non-radiative, k nr, rate constants and natural lifetimes, τ N, of the AC monomer in hexane and acetonitrile, obtained from the experimentally determined fluorescence quantum yields and fluorescence lifetimes, have been compared with those theoretically estimated. The closeness between these experimental and theoretical data, the small Stokes shifts, the mirror image relationship between the absorption and fluorescence spectra and the close correspondence between the absorption and fluorescence excitation spectra, provide good evidences that the emission of AC monomer occurs directly from its lowest singlet excited state. The mono- and multi-parametric analyses of the AC solvatochromism indicate that the polarity–polarizability, the hydrogen bond donor and the hydrogen bond acceptor properties of the solvent preferentially stabilize the singlet excited over the ground state. These analyses also reveal that photoexcitation reinforces the hydrogen bond donor and acceptor properties of the AC, becoming the pyridinic nitrogen atom more basic and the pyrrolic group more acid.

Structural and fluorescence quenching characterization of hematite nanoparticles

Nanoparticles of the dominant hematite form (α-Fe 2O 3) of iron oxide have been prepared by a simple route of dropping FeCl 3 solution into boiling water. The nanoparticles have been characterized by transmission electron microscopy (TEM), UV–visible electronic absorption spectroscopy, chemical stoichiometry, thermal analysis methods (TGA, DSC and DTA), XRD, FTIR and magnetic susceptibility measurements. Kinetic analysis of the DSC calorigram of thermal dehydration of the nanoparticles reveals one stage of the dehydration process of energy of activation of 29.0 kJ mol −1. The role of iron oxide nanoparticles in fluorescence quenching of coumarin thiourea derivatives (I–IV) was investigated at room temperature (296 K) by means of steady-state fluorescence spectroscopy. The quenching process was characterized by Stern–Volmer (S–V) plots which display a positive deviation from linearity. This could be explained by static and dynamic quenching models. The positive deviation in the S–V plot is interpreted in terms of ground-state complex formation model and sphere of action static quenching model. Various rate parameters for the fluorescence quenching process were determined by using the modified Stern–Volmer equation. The sphere of action static quenching model agrees very well with experimental results. Quenching constants for iron oxide nanoparticles are about four orders of magnitudes higher than quenching by Fe 3+ ions.

Silica embedded cobalt(0) nanoclusters: Efficient, stable and cost effective catalyst for hydrogen generation from the hydrolysis of ammonia borane

Cobalt(0) nanoclusters embedded in silica (Co@SiO 2) were prepared by a facile two-step procedure. In the first step, the hydrogenphosphate anion (HPO 4 2−) stabilized cobalt(0) nanoclusters were in situ generated from the reduction of cobalt(II) chloride during the hydrolysis of sodium borohydride (NaBH 4) in the presence of stabilizer. Next, HPO 4 2− anion-stabilized cobalt(0) nanoclusters were embedded in silica formed by in situ hydrolysis and condensation of tetraethylorthosilicate added as ethanol solution. Co@SiO 2 can be separated from the solution by vacuum filtration and characterized by UV–Vis electronic absorption spectroscopy, TEM, SEM-EDX, ATR-IR and ICP-OES techniques. Co@SiO 2 are found to be highly active and stable catalysts in the hydrolysis of ammonia borane (AB) even at low cobalt concentration and room temperature. They provide an initial turnover frequency of 13.3 min −1 and 24,400 total turnovers over 52 h in the hydrolysis of AB at 25.0 ± 0.5 °C. Moreover, Co@SiO 2 retain 72% and 74% of the initial activity after ten runs recyclability and five cycles reusability test in the hydrolysis of AB, respectively. The kinetics of hydrogen generation from the hydrolysis of AB catalyzed by Co@SiO 2 was studied depending on the catalyst concentration, substrate concentration, and temperature. The activation parameters of this catalytic reaction were also determined from the evaluation of the kinetic data.

Spectroscopic investigation of the VO2+/hyaluronate interaction

An oxovanadium(IV) complex was prepared by interaction of aqueous solutions of VOSO4·5H2O and sodium hyaluronate, at controlled pH-values, under nitrogen atmosphere, and subsequent precipitation with absolute ethanol. The complex formation and the characteristics of the VO2+/hyaluronate interactions were confirmed by vibrational (IR and Raman) and UV–vis electronic absorption spectroscopy. Only the carboxylate groups of the glucuronic acid moiety of the polymer are involved in coordination, acting as monodentate ligands. The suggested coordination is similar to that found in the analogous Cu(II), Mn(II) and Ni(II) complexes.

Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid) as an effective catalyst for Suzuki–Miyaura cross-coupling reactions in water

Palladium(0) nanoclusters stabilized by poly(4-styrenesulfonic acid-co-maleic acid), PSSA-co-MA, were generated in situ during the hydrolysis of ammonia–borane (AB) from the reduction of potassium tetrachloropalladate(II) in aqueous solution at room temperature. They were isolated from the reaction solution and characterized by UV–visible electronic absorption spectroscopy, TEM, SAED and XRD techniques. The PSSA-co-MA stabilized palladium(0) nanoclusters were used as catalyst in Suzuki–Miyaura cross-coupling reactions of various of arylbromides or aryl iodide with phenylboronic acid in water without any purification process after catalytic hydrolysis of AB. They show excellent catalytic activity in coupling of series of aryl bromides or aryl iodide with phenylboronic acid under the optimized reaction conditions in water. PSSA-co-MA stabilized palladium(0) nanoclusters provided turnover frequency of 1980 and 5940 h −1 in Suzuki–Miyaura coupling reactions of phenylboronic acid with p-bromoacetophenone or p-iodobenzene, respectively, which are the highest values ever reported for the Suzuki–Miyaura coupling reactions in water as sole solvent.

Hybrid hexagonal nanorods of metal nitride clusterfullerene and porphyrin using a supramolecular approach

Hexagonal nanorods of metal nitride clusterfullerene Sc3N@C80 (Ih) encapsulated in zinc meso-tetra(4-pyridyl) porphyrin (ZnTPyP) (Sc3N@C80-ZnTPyP nanorods) are prepared for the first time using a supramolecular approach. By introducing water as the solvent of cetyltrimethylammonium bromide (CTAB) surfactant, the effects of the solvent and the ratio of the reactants have been studied so as to control the length and size distribution of the Sc3N@C80-ZnTPyP nanorods. The encapsulation nature and hybrid structures of Sc3N@C80-ZnTPyP nanorods are confirmed by TEM, EDX, TGA and Raman spectroscopies. XRD study on the internal structure of Sc3N@C80-ZnTPyP nanorods suggests that ZnTPyP molecules tend to self-assemble in the axial direction. The UV-vis electronic absorption spectrum of Sc3N@C80-ZnTPyP nanorods shows broader and stronger absorptions in the visible region than those of the components Sc3N@C80 and ZnTPyP. The comparison of the UV-vis electronic absorption spectra of Sc3N@C80-ZnTPyP and C60-ZnTPyP nanorods reveals the influence of the electronic structures of fullerenes on the aggregative interactions between fullerene and ZnTPyP. The fluorescence emission intensity of Sc3N@C80-ZnTPyP nanorods exhibits a strong quenching (∼88%) compared to the pure ZnTPyP nanotubes, suggesting that photo-induced electron transfer from the excited ZnTPyP to Sc3N@C80 might occur. An electrochemical study of Sc3N@C80-ZnTPyP nanorods in comparison with those of ZnTPyP and Sc3N@C80 corroborate the hybrid nature of Sc3N@C80-ZnTPyP nanorods and reveal the interactions between Sc3N@C80 and ZnTPyP molecules.

Synthesis, Characterization and CMC Determination of some Double-Chain Surfactant-Cobalt(III) Complexes

Abstract Some new surfactant-cobalt(III) complex ions of the type, cis-[Co(X)2(C14H29NH2)2]3+ (where X = ethylenediamine or 2,2’ bipyridyl or 1,10-phenanthroline) and cis-α-[Co(trien)(C14H29NH2)2]3+ were synthesized and characterized by IR, NMR, UV-Visible electronic absorption spectra, elemental analysis and metal analysis. The critical micelle concentration (CMC) values of these surfactant-cobalt(III) complexes in aqueous solution were obtained from conductance measurements. Specific conductivity data (at 298, 308 and 318 K) served for the evaluation of temperature-dependent CMC and the thermodynamics of micellization (ΔG0 m, ΔH0 m, ΔS0 m).

Iron oxyhydroxide nanostructured in montmorillonite clays: Preparation and characterization

Akaganéite is a very rare iron oxyhydroxide in nature. It can be obtained by many synthetic routes, but thermohydrolysis is the most common method reported in the literature. In this work, akaganéite-like materials were prepared through the thermohydrolysis of FeCl 3·6H 2O in water and suspensions containing clay minerals. X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) data show that the clays determine the crystal phase and size of the iron oxyhydroxide crystals. According to XRD and FTIR data, β-FeO(OH) (akaganéite) is the main metal oxyhydroxide phase. Considering the small basal spacing ( d 0 0 1 ) displacement observed when comparing the XRD patterns of pristine clays with the composites containing β-FeO(OH), the iron oxyhydroxide should be mostly located on the basal and edge surfaces of the clay minerals. UV–Vis electronic absorption spectra indicate that the preferred phase of the iron oxyhydroxide is determined by the nature of the clay minerals.

Solvent effects on the electronic and vibrational properties of high-valent oxomolybdenum(V) 5,10,15-triphenylcorrole probed by UV-visible and resonance Raman spectroscopy

Solution UV-visible electronic absorption and resonance Raman (RR) scattering spectra in 25 aprotic organic solvents have been measured and analyzed for a high-valent molybdenum( V ) oxo complex of 5,10,15-triphenylcorrole, (MoVO)CorPh3 . Optical absorption data in the visible region show a significant positive solvatochromism upon increasing solvent polarizability (ca. 660 cm-1 for the violet Soret band on going from acetonitrile to carbon disulfide), described by an excellent linear correlation between the bathochromic shifts of corrole π → π* electronic transitions and the solvent refractive index [Formula: see text]. Isotope labeling of the terminal oxo group with 18 O revealed the oxo-Mo(V) stretch of (MoVO)CorPh3 to vibrate at frequency ν(MoVO) ≈ 970 cm-1 [Δ(16O-18O) = 46 cm-1] , consistent with a MoV≡O triple bond. This vibration is greatly enhanced in the RR spectra with excitations within the Soret absorption band and its frequency is sensitive to solute-solvent interactions that weaken the MoV≡O triple bond by inhibiting O2- → Mo5+ electron donation. The ν(MoVO) frequency decreases in direct proportion to the Swain's solvent polarity parameter (A + B), from 969.4 cm-1 in n-hexane solution down to 955.6 cm-1 in dimethyl sulfoxide solution. However, only weak linear correlation was found when the ν(MoVO) frequencies were plotted as a function of the Gutmann's solvent acceptor numbers (ANs). A molecular association occurs between chloroform and (MoVO)CorPh3 through MoV≡O⋯H-CCl3 hydrogen-bonding interactions, manifested as an upshift of the ν(MoVO) RR band in deuteriochloroform solution. The ν(MoVO) stretching frequencies of (MoVO)CorPh3 and its fluorinated derivative (MoVO)Cor(Ph(CF3)2)3 {Cor(Ph(CF3)2)3 = 5,10,15-tris-[3,5-bis(trifluoromethyl)phenyl]corrole} are compared, and the increased strength of the MoV≡O bond in the latter oxo-Mo(V) species is attributed to the cis effect of the electron-withdrawing -C6H3(CF3)2 groups, as judged by a 6 cm-1 elevation of the ν(MoVO) frequency. Raman excitation profiles of ν(MoVO) and corrole skeletal vibrations show the presence of charge-transfer and π → π* electronic transitions within the Soret absorption band of oxomolybdenum( V ) corroles.