The attachment of an ethyne substituent in the para position of phenylisocyanide, CNPhpC≡CH, enables the isocyanide to replace carbonyl ligands in the coordination sphere of common technetium(I) starting materials such as (NBu4)[Tc2(μ-Cl)3(CO)6]. The ligand exchange proceeds under thermal conditions and finally forms the corresponding hexakis(isocyanide)technetium(I) complex. The product undergoes a copper-catalyzed cycloaddition (“Click” reaction), e.g., with benzyl azide, which gives the [Tc(CNPhazole)6]+ cation. The free, uncoordinated “Click” product is obtained from a reaction of the corresponding tetrakis(CNPhazole)copper(I) complex and NaCN. It readily reacts with mer-[Tc(CO)3(tht)(PPh3)2](BF4) (tht = tetrahydrothiophene) under exchange of the thioether ligand. Alternatively, [Cu(CNPhazole)4]+ can be used as a transmetalation reagent for the synthesis of the hexakis(isocyanide)technetium(I) complex, which is the preferable approach for the synthesis of the technetium complex with the short-lived nuclear isomer 99mTc, and a corresponding protocol for [99mTc(CNPhazole)6]+ is reported. The 99Tc and copper complexes have been studied by single-crystal X-ray diffraction and/or spectroscopic methods including IR and multinuclear NMR spectroscopy.

Previously reported carbazole-bis(tetrazole) (CzTR) ligands (where R = iPr and CH2-2,4,6-C6H2Me3) were used to synthesize air-stable, six-coordinate, octahedral bis-ligand Fe(II) complexes (CzTR)2Fe. The synthesis and characterization of these complexes using 1H nuclear magnetic resonance (NMR), X-ray crystallography, Mössbauer spectroscopy, and density functional theory (DFT) calculations are reported. Analysis of the magnetic properties revealed that the isopropyl derivative displays thermally induced spin crossover (SCO) over a temperature range of 150–350 K. This transition appears as an abrupt two-step transition in the solid state but simplifies to a smooth one-step transition in solution. The two-step transition in the solid state has been postulated to be due to lattice and solvation effects. In contrast, the slightly bulkier substituted CH2-2,4,6-C6H2Me3 (CH2Mes) Fe complex displays dramatically different magnetic behavior with no SCO and magnetic data suggesting low-spin Fe(II) with a possible TIP contribution. DFT calculations support the postulate that the change in magnetic behavior is primarily due to the nature of the ligand substituents.

Due to the higher energy density, high thermal stability, and low cost, LiNi0.5Mn1.5O4 (LNMO) spinel, with a large voltage operating window, has been one of the most promising cathode materials for lithium-ion batteries (LIBs). However, the interfacial reaction between the cathode and electrolyte and the two-phase reaction within the bulk of LNMO would destroy the original structure and lead to capacity deterioration, posing a significant challenge. Therefore, the way to suppress the transition-metal (TM) dissolution in LNMO has attracted much attention. However, the ordered/disordered phase regulation by metal atom doping to prohibit TM dissolution has not been extensively explored. Herein, a Ge-doping strategy is proposed to adjust the ratio of disordered/ordered phases in LNMO, resulting in exceptional structural stability. For the modified spinel cathode, there is almost no voltage drop and the capacity retention is up to 92.2% over 1000 cycles at 1C. These results demonstrate that incorporating Ge into LNMO forms a robust structure that effectively increases the amount of Mn4+ while blocking the diffusion of TM ions. In addition, Ge-doping also protects the bulk from further reactions with electrolytes, significantly enhancing the interfacial stability and relieving voltage decay in cycling. This approach can also be applied to design other high-stability cathodes through ordered/disordered phase regulation.

Based on the principle of heterogeneous catalysis for water electrolysis, electrocatalysts with appropriate electronic structure and photothermal property are expected to drive the oxygen evolution reaction effectively. Herein, amorphous NiSx-coupled nanourchin-like Co3O4 was prepared on nickel foam (NiSx@Co3O4/NF) and investigated as a electrocatalyst for photothermal-assisted oxygen evolution reaction. The experimental investigations and simulant calculations jointly revealed NiSx@Co3O4/NF to be of suitable electronic structure and high near-infrared photothermal conversion capability to achieve the oxygen evolution reaction advantageously both in thermodynamics and in kinetics. Relative to Co3O4/NF and NiSx/NF, better oxygen evolution reaction activity, kinetics, and stability were achieved on NiSx@Co3O4/NF in 1.0 M KOH owing to the NiSx/Co3O4 synergetic effect. In addition, the oxygen evolution reaction performance of NiSx@Co3O4/NF can be obviously enhanced under near-infrared light irradiation, since NiSx@Co3O4 can absorb the near-infrared light to produce electric and thermal field. For the photothermal-mediated oxygen evolution reaction, the overpotential and Tafel slope of NiSx@Co3O4/NF at 50 mA cm–2 were reduced by 23 mV and 13 mV/dec, respectively. The present work provides an inspiring reference to design and develop photothermal-assisted water electrolysis using abundant solar energy.

A simple and reliable method is developed to fabricate Ag-nanoparticle-decorated Co(OH)2 nanoflowers grafted on polyacrylonitrile (PAN) nanopillar arrays as uniform and sensitive surface-enhanced Raman scattering (SERS) substrates. First, Co(OH)2-nanosheet-assembled nanoflowers are achieved on the highly uniform PAN nanopillar arrays via electrochemical deposition. Then, Ag nanoparticles (Ag-NPs) are decorated onto the Au-nanoparticle-precoated Co(OH)2 nanoflowers based on a spontaneous redox reaction (SRR) between the silver ions and Co(OH)2 nanosheets at room temperature. Ag-NPs can be successfully in situ synthesized on the Co(OH)2 nanoflowers, and Au nanoparticles precoated on the surface of the Co(OH)2 nanosheets can ensure that the Co(OH)2 nanoflower structure does not collapse. Because of the highly uniform PAN nanopillar arrays and the high-density sub-10 nm gaps between the neighboring Ag-NPs on the surface of the Co(OH)2 nanoflowers, the hierarchical three-dimensional Ag@Co(OH)x grown on PAN nanopillar arrays can produce a reproducible and sensitive SERS effect. To verify the SERS performance of the substrate, 4-aminothiophenol (4-ATP) is used as the probe molecule, and the Ag@Co(OH)x grown on PAN nanopillar arrays is employed as the SERS substrate. As a result, 4-ATP concentrations as low as 10–10 M can still be identified, exhibiting high SERS activity. Additionally, the relative standard deviation value of the main characteristic peak of 10–5 M 4-ATP is 9.43%, indicating good uniformity of the SERS signal of the substrate. The SRR between silver ions and Co(OH)2 can provide a simple route to prepare heterostructures as SERS substrates, which has great potential for application in the field of analysis.

Understanding the diverse reactivities of vitamin B12 and its derivatives, collectively called cobalamins, requires detailed knowledge of their geometric and electronic structures. Electronic absorption (Abs) and resonance Raman (rR) spectroscopies have proven invaluable in this area, particularly when used in concert with computational techniques such as density functional theory (DFT). There remain, however, lingering uncertainties in the computational description of electronic excited states of cobalamins, particularly surrounding the vibronic coupling that impacts the Abs bandshapes and gives rise to rR enhancement of vibrational modes. Past computational analyses of the vibrational spectra of cobalamins have either neglected rR enhancement or calculated rR enhancement for only a small number of modes. In the present study, we used the recently developed ORCA_ASA computational tool in conjunction with the popular B3LYP and BP86 functionals to predict Abs bandshapes and rR spectra for vitamin B12. The ORCA_ASA/B3LYP-computed Abs envelope in the visible spectral region and rR spectra of vitamin B12 agree remarkably well with our experimental data, while BP86 fails to reproduce both. This finding represents a significant advance in our understanding of how these two commonly used density functionals differently model the electronic properties of cobalamins. Guided by the computed frequencies for the Co–C stretching and Co–C–N bending modes, we identified, for the first time, isotope-sensitive features in our rR spectra of 12CNCbl and 13CNCbl that can be assigned to these modes. A normal coordinate analysis of the experimentally determined Co–C stretching and Co–C–N bending frequencies indicates that the Co–C force constant for vitamin B12 is 2.67 mdyn/Å, considerably larger than the Co–C force constants reported for alkylcobalamins.

Selective oxidation of aniline to azobenzene with a higher economic value is significant for modern industrial production. However, the high reaction temperature and undefined catalytic reaction center always limit the promotion of this reaction. Here, we designed and synthesized a new [P4MoV6O31]12–-based cobalt-containing complex (Hbiz)5{Co(H2O)3[Co(H2O)2]2}{Co[Mo6O12(OH)3(PO4)(HPO4)3][Mo6O12(OH)3(PO4)2(HPO4)2]}·3H2O (1; biz = benzimidazole) under solvothermal conditions. Using 1 as the photocatalyst, the visible-light-driven conversion of aniline to azobenzene at room temperature was realized for the first time (conversion rate 97%, selectivity 96% of azobenzene, reaction time of 12 h). Additionally, real sunlight irradiation can produce a comparable outcome in 48 h. The mechanism investigation manifested that the Mo and Co centers in 1 acted as Brönsted and Lewis acid centers, synergistically promoting the aniline oxidation reaction. This research advances the application of polyoxometalate-based photocatalysts while also offering a sustainable and effective method for producing azobenzene.

The self-reduction mechanism in pyrophosphate phosphors is currently explained through nonequivalent substitution for charge compensation. Nevertheless, the impact of oxygen vacancies on the self-reduction enhancement requires further investigation. Herein, heterovalent Ba1–xZn1–yP2O7:xEu2+/3+, yMg phosphors with rigid structures were prepared through conventional solid-phase technology in air. The cation substitution strategy leads to different chemistry electronegativity and adjustable crystal field environments and creates vacancy defects. Crystal structure and component analysis indicate the gradual phase segregation change from BaZnP2O7 to BaMgP2O7 with increasing Mg2+ content. The CIE coordinates that are tuned from (0.514, 0.334) to (0.326, 0.152) and realize color-tunable emission from red-orange to blue-violet can be used as multicolor functional materials. Besides, the phosphor demonstrates its maximum Sa of 0.4725% K–1 (498 K) and Sr of 1.376% K–1 (423 K). These results demonstrate that the phosphors have the potential for contactless optical temperature measurement and anticounterfeiting. This work not only investigates the self-reduction of the Eu3+ → Eu2+ phenomenon but also provides a supplementary explanation and data support to complete the effect of the oxygen vacancy on self-reduction.

A new quaternary sulfide telluride, Ba6Fe2Te3S7, was synthesized by a solid-state reaction, and its crystal structure is novel. X-ray diffraction data on powder and single crystals reveal an orthorhombic lattice with a = 9.7543(3) Å, b = 18.2766(6) Å, and c = 12.0549(4) Å, and the noncentrosymmetric space group Cmc21 (No. 36). The properties of the compound were studied by magnetic susceptibility investigations, specific heat measurements, Mössbauer spectroscopy, and density functional theory calculations. Assuming Ba2+ and, as verified by the Mössbauer spectra, Fe3+, the charge balance requires the presence of a polytelluride, suggested to be a straight-chain [Te34–] polyanion. Further, the crystal structure contains [Fe2S7]8– dimers of two vertex-sharing tetrahedra, with a nearly linear Fe–S–Fe atom arrangement. The dimer exhibits antiferromagnetic coupling, with a coupling constant J = −10.5 meV (H = −2JS1S2) and S = 5/2, resulting in a spin singlet ground state. The interdimer magnetic interaction is so weak that the magnetic dimers can be treated as individuals.

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Six new solvent-free, homoleptic paramagnetic tris(alkyl)lanthanides Ln{C(SiHMe2)3}3 (1Ln) and Ln{C(SiHMe2)2Ph}3 (2Ln) (Ln = Gd, Dy, and Er) were synthesized to investigate the magnetic properties of 4f organometallic compounds stabilized by secondary Ln↼H–Si and benzylic interactions. The unit cell of 1Gd contains one independent molecule (Z = 2), while 1Dy and 1Er crystallize with four independent isostructural molecules per unit cell (Z = 16). In all molecules, as in other 1Ln compounds, the three tris(dimethylsilyl)methyl ligands form a trigonal planar LnC3 core, and six secondary interactions involving Ln↼H–Si bonding in Ln{C(SiHMe2)3}3 form above and below the equatorial plane. Two and five crystallographically independent molecules of each 2Ln (2Gd, Z = 8; 2Dy, Z = 20) form with three π-coordinated phenyl groups in addition to either one or two secondary Ln↼H–Si interactions per molecule. The packing of these midseries organolanthanide compounds contrasts the single crystallographically unique molecules in previously reported La{C(SiHMe2)3}3 (1La, Z = 2, Z′ = 1) and La{C(SiHMe2)2Ph}3 (2La, Z = 2, Z′ = 1/3). 2La doped with 2Dy can adopt the crystallographic structure of 2La, which promotes magnetic properties, namely a higher χmT value at low temperatures as well as stronger magnetic anisotropy. The ac susceptibility data for 10% 2Dy doped into 2La suggests slow relaxation at low temperatures with a relaxation barrier of ∼45 K. The computed saturated magnetization of 1Er (M ≈ 4.5 μB) and 1Dy (M ≈ 6 μB) matches the experimental values, while the computed value for 2Dy better matches the value measured for 2Dy diluted in 2La (M ≈ 5 μB). Gas-phase calculations predict that the ground-state and first excited-state multiplet separations are larger for 1Er than 2Er, while the ordering for dysprosium is 1Dy > 2Dy.

Coordination polymers with external stimuli-responsive structural transformation acquired paramount importance in the advanced material research field due to their eye-catching application to deal with the existing challenging issue, and Co(II) metal complex with d7 electronic configuration is a renowned candidate for kinetic accountability and has the potentiality of structural transformation. Bearing these factors in mind, here, a Co(II) congener of a previously reported high hydrogen-adsorbing Cu(II)-based coordination polymer (CP), {[Cu(4-bpe)(2-ntp)]}n [where 2-ntp2– = 2-nitroterephthalate and 4-bpe = 1,2-bis-(4-pyridyl)ethane], has been synthesized to study the metal change impact on hydrogen adsorption and solvent-induced structural transformation with their impact on hydrogen uptake. This modified framework has a 2D + 2D → 3D inclined polycatenated framework as comparable to our previously published Cu(II) framework. Here, on the variation of different solvents, the labile Co(II)-containing framework exhibits a structural change through single-crystal to single-crystal (SC–SC) structural transformation and results in three new framework structures. All four frameworks are structurally characterized by elemental analysis, IR, PXRD, TGA, and single-crystal X-ray diffraction. The desolvated parent framework with exposed metal centers exhibits excellent results of H2 adsorption of 1.3 wt % (145 cc/g) at 77 K and pressure of 1 bar with structural sustainability and CO2 uptake of 130 cc/g at 195 K and 1 bar. For the other three solvent-mediated structural derivatives, H2 and CO2 adsorption have been studied, and the results are correlated with their structure.

Four types of bis- and tris(tetra-armed cyclen)s were prepared. 2MF is a bis(tetra-armed cyclen) with electron-rich side arms (three 4-methoxybenzyl groups) and electron-deficient side arms (three 3,5-difluorobenzyl groups), connected by a 4,4′-dimethyl-1,1′-biphenyl moiety. 3MFM is a tris(tetra-armed cyclen) with 4-methoxybenzyl and 3,5-difluorobenzyl groups introduced on both ends and the central cyclen, respectively. 4MFM is a V-shaped analogue of 3MFM. 3FMF is a tris(tetra-armed cyclen) where the aromatic side arms at both ends and the central cyclen of 3MFM are exchanged. The regioselective coordination of silver(I) ions by these ligands is reported. Initially, we added Ag+ ions to a compound (2MF) that consists of tetra-armed cyclen with 4-methoxybenzyl groups as an electron-donating substituent on the aromatic rings and 3,5-difluorobenzyl groups as an electron-withdrawing substituent. 1H NMR and 19F{1H} NMR spectroscopy exhibited that the cyclen with the 4-methoxybenzyl groups formed a complex with Ag+ ions first, followed by the cyclen with the 3,5-difluorobenzyl groups. Next, we employed a compound (3MFM) with three cyclen units, where the cyclen at each end was functionalized with three 4-methoxybenzyl groups, and the central cyclen was functionalized with two 3,5-difluorobenzyl groups. Upon adding Ag+ ions, we observed that the cyclen units at both ends formed complexes with Ag+ ions initially, followed by the central cyclen forming a complex with Ag+ ions. When we used 4MFM, which is a V-shaped compound, the Ag+-induced-1H NMR chemical shift changes are almost the same results as the 3MFM. Furthermore, we synthesized a compound (3FMF) by interchanging the substituents on the cyclen units at the ends and the center. Interestingly, the order of the complex formation was reversed in this compound. These results demonstrated that tuning the electron density on the aromatic side arms through substituents makes it possible to achieve regioselective coordination with Ag+ ions in bis- or tris(tetra-armed cyclen)s.

The rational design of an oxygen electrocatalyst with low cost and high activity is greatly desired for realization of the practical water-splitting industry. Herein, we put forward a rational method to construct nonprecious-metal catalysts with high activity by designing the microstructure and modulating the electronic state. Iron (Fe)-doped Ni2P hollow polyhedrons decorated with nitrogen-doped carbon (Fe-Ni2P/NC HPs) are prepared by a sequential metal–organic-framework-templated strategy. Benefiting from the strong electronic coupling, rapid charge-transfer capability, and abundant catalytic active sites, the obtained Fe-Ni2P/NC HPs exhibit an impressive electrocatalytic performance toward the oxygen evolution reaction (OER) with an ultralow overpotential of 228 mV at a current density of 10 mA cm–2 and a small Tafel slope of 33.4 mV dec–1, superior to the commercial RuO2 and most reported electrocatalysts. Notably, this catalyst also shows long durability with an almost negligible activity decay over 210 h for the OER. Combining density functional theory calculations with experiments demonstrates that the doped Fe and the incorporated carbon effectively modulate the electronic structure, enhance the conductivity, and greatly reduce the energy barrier of the rate-determining step in the process of OER. Thus, fast OER kinetics is realized. Moreover, this synthetic strategy can be extended to the synthesis of Fe-NiS2/NC HPs and Fe-NiSe2/NC HPs with excellent OER performance and long-term durability. This work furnishes an instructive idea in pursuit of nonprecious-metal materials with robust electrocatalytic activity and long durability.

In the present study, we fabricated hollow cubic CuxO nanoparticles (∼23 nm) incorporated with CNF (HC-CuxO/CNF) through controlled thermal oxidation of solid cubic Cu2O nanoparticles (∼21 nm) supported on carbon nanofibers (SC-Cu2O/CNF) under airflow, exploiting the nanoscale Kirkendall effect. These hollow CuxO nanocubes with increased surface areas exhibited outstanding catalytic activity for unsymmetrical chalcogenide synthesis under ligand-free conditions.

The effects of temperature and composition on the structural and electronic properties of chalcogenide perovskite (CP) materials AZrX3 (A = Ba, Sr, Ca; X = S, Se) in the distorted perovskite (DP) phase are investigated using ab initio molecular dynamics (AIMD) accelerated by machine-learned force fields. Long-range van der Waals (vdW) interactions, incorporated into the Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional using the DFT-D3 scheme, are found to be crucial for achieving correct predictions of structural parameters. Our calculations show that the distortion of the DP structure with respect to the parent cubic (C) phase, realized in the form of interoctahedral tilting, decreases with the increasing size of the A cations. The tendency for a gradual transformation of the DP-to-C phase with increasing temperature is shown to be strongly composition-dependent. The transformation temperature decreases with the size of cation A and increases with the size of anion X. Thus, within the range of the temperatures considered here (300–1200 K), a complete transformation is observed only for BaZrS3 (∼600 K) and BaZrSe3 (∼900 K). The computed band gap of CPs is shown to monotonically decrease with increasing temperature, and the magnitude of this decrease is found to be proportional to the extent of the thermally induced changes in the internal structure. Diverse factors affecting the magnitude of band gaps of CP materials are analyzed.

We report the synthesis and the assessment of the anticancer potential of two series of diruthenium biscyclopentadienyl carbonyl complexes. Novel dimetallacyclopentenone compounds (2–4) were obtained (45–92% yields) from the thermal reaction (PhCCPh exchange) of [Ru2Cp2(CO)(μ-CO){μ-η1:η3-C(Ph)═C(Ph)C(═O)}], 1, with alkynes HCCR [R = C5H4FeCp (Fc), 3-C6H4(Asp), 2-naphthyl; Cp = η5-C5H5, Asp = OC(O)-2-C6H4C(O)Me]. Protonation of 1–3 by HBF4 afforded the corresponding μ-alkenyl derivatives 5–7, in 40–86% yields. All products were characterized by IR and NMR spectroscopy; moreover, cyclic voltammetry (1, 2, 5, 7) and single-crystal X-ray diffraction (5, 7) analyses were performed on representative compounds. Complexes 5–7 revealed a cytotoxic activity comparable to that of cisplatin in A549 (lung adenocarcinoma), SW480 (colon adenocarcinoma), and ovarian (A2780) cancer cell lines, and 2, 5, 6, and 7 overcame cisplatin resistance in A2780cis cells. Complexes 2, 5, and 7 (but not the aspirin derivative 6) induced an increase in intracellular ROS levels. Otherwise, 6 strongly stabilizes and elongates natural DNA (from calf thymus, CT-DNA), suggesting a possible intercalation binding mode, whereas 5 is less effective in binding CT-DNA, and 7 is ineffective. This trend is reversed concerning RNA, and in particular, 7 is able to bind poly(rA)poly(rU) showing selectivity for this nucleic acid. Complexes 5–7 can interact with the albumin protein with a thermodynamic signature dominated by hydrophobic interactions. Overall, we show that organometallic species based on the Ru2Cp2(CO)x scaffold (x = 2, 3) are active against cancer cells, with different incorporated fragments influencing the interactions with nucleic acids and the production of ROS.

Polyoxometalates have attracted significant interest owing to their structural diversity, redox stability, and functionality at the nanoscale. In this work, density functional theory calculations have been employed to systematically study the accuracy of various exchange–correlation functionals in reproducing experimental redox potentials, U0Red in [PW11M(H2O)O39]q− M = Mn(III/II), Fe(III/II), Co(III/II), and Ru(III/II). U0Red calculations for [PW11M(H2O)O39]q− were calculated using a conductor-like screening model to neutralize the charge in the cluster. We explicitly located K+ counterions which induced positive shifting of potentials by > 500 mV. This approximation improved the reproduction of redox potentials for Kx[XW11M(H2O)O39]q−x M = Mn(III/II)/Co(III/II). However, uncertainties in U0Red for Kx[PW11M(H2O)O39]q−x M = Fe(III/II)/Ru(III/II) were observed because of the over-stabilization of the ion-pairs. Hybrid functionals exceeding 25% Hartree–Fock exchange are not recommended because of large uncertainties in ΔU0Red attributed to exaggerated proximity of the ion-pairs. Our results emphasize that understanding the nature of the electrode and electrolyte environment is essential to obtain a reasonable agreement between theoretical and experimental results.

A 0.25% iron (Fe3+)-doped LiGaO2 phosphor was synthesized by a high-temperature solid-state reaction method. The phosphor was characterized utilizing X-ray diffraction (XRD), scanning electron microscopy (SEM), high-pressure photoluminescence, and photoluminescence decay measurement techniques using diamond anvil cells (DACs). The powder X-ray analysis shows that the phosphor is a β polymorph of LiGaO2 with an orthorhombic crystallographic structure at room temperature. The SEM result also confirms the presence of well-dispersed micro-rod-like structures throughout the sample. The photoluminescence studies in the near-infrared (NIR) range were performed at ambient, low-temperature, and high-pressure conditions. The synthesized phosphor exhibits a photoluminescence band around 746 nm related to the 4T1 → 6A1 transition with a 28% quantum efficiency at ambient conditions, which shifts toward longer wavelengths with the increase of pressure. The excitation spectra of Fe3+ are very well fitted with the Tanabe–Sugano crystal-field theory. The phosphor luminescence decays with a millisecond lifetime. The high-pressure application transforms the β polymorph of LiGaO2 into a trigonal α structure at the pressure of about 3 GPa. Further increase of pressure quenches the Fe3+ luminescence due to the amorphization process of the material. The prepared phosphor exhibits also mechanoluminescence properties in the NIR spectral region.

To study the switching properties of photochromes, we undertook the synthesis and characterization of several ruthenium organometallic complexes of the type [Ru(Cp*)(dppe)(C≡C-SP)] or [Ru(CO)(dppe)(PPh3)Cl(CH═CH-SP)], where SP = spiropyran. The spectroscopic and electrochemical properties of the complexes were determined by careful cyclic voltammetric and spectroelectrochemical experiments. Whereas the mononuclear alkynyl ruthenium complexes undergo one-electron oxidations localized over the metal alkynyl moiety, the oxidation of the mononuclear vinyl ruthenium complexes is centered on the indoline moiety of the spiropyran. Through these studies, we demonstrate access to several stable redox states, in addition to switching states attained via acidochromism and/or photoisomerization.