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Ganguly T, Das S, Maity D, Baitalik S. Luminescent Ruthenium-Terpyridine Complexes Coupled with Stilbene-Appended Naphthalene, Anthracene, and Pyrene Motifs Demonstrate Fluoride Ion Sensing and Reversible Trans-Cis Photoisomerization. Inorg Chem 2024; 63:6883-6897. [PMID: 38567656 DOI: 10.1021/acs.inorgchem.4c00339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
A new family of luminescent heteroleptic Ru(II)-terpyridine complexes coupled with stilbene-appended naphthalene, anthracene, and pyrene motifs is reported. Each of the complexes features moderately intense emission at room temperature having a lifetime of 16.7 ns for naphthalene and 11.4 ns for anthracene, while a substantially elevated lifetime of 8.3 μs was observed for the pyrene derivative. All the three complexes display a reversible couple in the positive potential window due to Ru2+/Ru3+ oxidation but multiple reversible and/or quasi-reversible peaks in the negative potential domain because of the reduction of the terpyridine moieties. All the complexes selectively sense F- among the studied anions via the intermediary of different noncovalent interactions. The interaction event is monitored through absorption, emission, and 1H and 19F NMR spectroscopy. Additionally, upon utilizing the stilbene motif, reversible trans-cis isomerization of the complexes has been undertaken upon alternate treatment of visible and UV light so that the complexes can act as potential photomolecular switches. We also carried out the anion sensing characterization of the cis form of the complexes. Theoretical calculation employing density functional theory is also executed for a selective complex (naphthalene derivative) to elucidate different noncovalent interactions that are operative during the complex-fluoride interplay.
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Affiliation(s)
- Tanusree Ganguly
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Soumi Das
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Dinesh Maity
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
- Department of Chemistry, Katwa College, Purba Bardhaman, West Bengal 713130, India
| | - Sujoy Baitalik
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
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Bhattacharya S, Pal P, Baitalik S. Design of molecular sensors and switches based on luminescent ruthenium-terpyridine complexes bearing active methylene and triphenylphosphonium motifs as anion recognition sites: experimental and DFT/TD-DFT investigation. Dalton Trans 2024; 53:1307-1321. [PMID: 38115813 DOI: 10.1039/d3dt03681b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Synthesis, characterization and thorough investigation of the photophysical and electrochemical properties of a new category of emissive homo- and heteroleptic Ru(II)-complexes derived from the [4'-(p-triphenylphosphonium methyl phenyl)-2,2':6',2''-terpyridine]bromide (tpy-PhCH2PPh3Br) ligand have been executed in this work. Incorporation of the PhCH2PPh3+Br- group at the terpyridine motif appropriately adjusts the triplet metal-to-ligand charge transfer (3MLCT) and metal-centered (3MC) excited states so that the complexes luminesce at room temperature (RT) having lifetimes within the range of 6.82-9.63 ns. The RT emission characteristics of the complexes get further enhanced via aggregation phenomena through the use of different solvent/non-solvent mixtures (DMSO/H2O and DMSO/PhCH3 mixtures). Temperature dependent emission spectral measurements indicate that the emission intensity, quantum yield and lifetime increase upon dropping down the temperature, thereby designated as the on-state, while the increase of temperature causes a reduction of the said properties, indicating the off-state and the process is fully reversible. Taking advantage of the active methylene group coupled with a phosphonium motif, anion sensing characteristics of the complexes are investigated systematically in DMSO through the use of various optical channels and spectroscopic tools. The complexes are very much sensitive to fluoride and to a lesser extent acetate and dihydrogen phosphate among the studied anions. In essence, the complexes function as sensors for temperature and fluoride ion. Computational investigations were also executed via density functional theory (DFT) and time-dependent (TD)-DFT to obtain a clear understanding of the electronic structures of the metalloreceptors, appropriate assignment of the spectral bands and their mode of interaction with selected anions.
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Affiliation(s)
- Sohini Bhattacharya
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India.
| | - Poulami Pal
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India.
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
| | - Sujoy Baitalik
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India.
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Sahoo A, Bar M, Biswas R, Abedin T, Baitalik S. Modulation of ground and excited state properties of ruthenium complexes through sequential incorporation of metal into a polypyridyl-imidazole bridging ligand. Dalton Trans 2023; 52:15896-15906. [PMID: 37840479 DOI: 10.1039/d3dt02757k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
A polypyridyl-imidazole-based bridging ligand, 2-(4-(4,5-di(pyridine-2-yl)-1H-imidazole-2-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (phen-H2PhImz-bpy), possessing three bidentate coordinating sites, has been designed in this work. The bridging ligand is employed to synthesize mono-, bi-, and trimetallic Ru(II) complexes in combination with terminal bipyridine units for the systematic modulation of photophysical and redox properties upon sequential incorporation of the metal unit into the bridge. All the compounds are characterized via NMR spectroscopy and electrospray ionization mass spectrometry. Absorption and both steady-state and time-resolved emission spectroscopic investigations of the ligand as well as Ru(II) complexes are thoroughly conducted in different solvents. The redox behaviors of the complexes are examined through cyclic voltammetry (CV) in acetonitrile. The focus of the investigation is centered on the systematic modulation of MLCT absorption and emission as well as the redox behavior of the complex entity upon the gradual incorporation of the Ru2+ unit into the complex backbone. The emission energy, quantum yield and lifetime are found to decrease systematically with an increase in the Ru2+ unit in the complex backbone and a linear relationship is observed in each case. A good correlation is also observed between the emission energies of complexes with their respective ΔE1/2 values (the difference between the first oxidation and first reduction potential).
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Affiliation(s)
- Anik Sahoo
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Manoranjan Bar
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Raju Biswas
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Tuhin Abedin
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sujoy Baitalik
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
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Das S, Pal P, Ganguly T, Baitalik S. Influences of Both N,N,N- and N,N,C-Coordination Modes of Tolyl-terpyridine on the Photophysical Properties of Cyclometalated Ru(II) Complexes: Combined Experimental and Theoretical Investigations on Acid/Base-Dependent Reversible Cyclometalation. Inorg Chem 2023; 62:12872-12885. [PMID: 37506326 DOI: 10.1021/acs.inorgchem.3c01523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
With the goal of developing a new strategy for the synthesis of luminescent Ru(II) complexes, we have prepared herein a new set of bis-tridentate complexes of the type [(py-bpy-Ph-X)Ru(tpy-PhCH3)]ClO4 (X = -CH3, -CH2Br, and -CHO) incorporating both non-cyclometalated and cyclometalated coordination motifs of two isomeric forms of methylphenyl-terpyridine (tpy-PhCH3). Thorough characterization of the synthesized complexes is carried out using standard analytical tools and single crystal X-ray diffraction. Detailed investigations on their photophysical and electrochemical behaviors are carried out in MeCN. The presence of a carbanionic center in the cyclometalating unit increases the absorption spectral window of the complexes into a longer-wavelength region. The complexes also exhibit room-temperature luminescence in the NIR domain with enhanced excited-state lifetimes (up to 20.1 ns) compared to their non-cyclometalated counterpart, [Ru(tpy-PhCH3)2]2+. In the presence of acid, the non-coordinated nitrogen atom in the secondary coordination sphere of the complexes allows fine-tuning of the absorption and emission spectral properties. Excess acid induces de-coordination of the Ru-C bond, which is signaled by a remarkable alteration of their spectral profiles. Cleavage of the Ru-C bond is also possible upon treating the acidified solution of the complexes with visible light. Restoration of the Ru-C bond is again feasible upon treating the solution with base at an elevated temperature (∼70 °C). In essence, "on-off" and "off-on" switching of emission is facilitated upon alternating treatment of the Ru(II) complexes with acid, base, and temperature. DFT and TD-DFT calculations are also performed for assignments of the spectral bands as well as to understand structural changes associated with the switching behaviors of the complexes.
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Affiliation(s)
- Soumi Das
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Poulami Pal
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
- School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A & B Raja S C Mullick Road, Kolkata 700032, India
| | - Tanusree Ganguly
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Sujoy Baitalik
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
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Ganguly T, Pal P, Maity D, Baitalik S. Synthesis, characterization and emission switching behaviors of styrylphenyl-conjugated Ru(II)-terpyridine complexes via aggregation and trans–cis photoisomerization. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
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Deb S, Sahoo A, Karmakar S, Baitalik S. Multi-channel anion sensing behaviour of a Ru(II)-bipyridine complex based on benzothiazolyl pyrazole ligand: experimental and implication of machine learning tools for data prediction. Inorganica Chim Acta 2023. [DOI: 10.1016/j.ica.2023.121451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
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Development and Application of Ruthenium(II) and Iridium(III) Based Complexes for Anion Sensing. Molecules 2023; 28:molecules28031231. [PMID: 36770897 PMCID: PMC9920910 DOI: 10.3390/molecules28031231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 01/31/2023] Open
Abstract
Improvements in the design of receptors for the detection and quantification of anions are desirable and ongoing in the field of anion chemistry, and remarkable progress has been made in this direction. In this regard, the development of luminescent chemosensors for sensing anions is an imperative and demanding sub-area in supramolecular chemistry. This decade, in particular, witnessed advancements in chemosensors based on ruthenium and iridium complexes for anion sensing by virtue of their modular synthesis and rich chemical and photophysical properties, such as visible excitation wavelength, high quantum efficiency, high luminescence intensity, long lifetimes of phosphorescence, and large Stokes shifts, etc. Thus, this review aims to summarize the recent advances in the development of ruthenium(II) and iridium(III)-based complexes for their application as luminescent chemosensors for anion sensing. In addition, the focus was devoted to designing aspects of polypyridyl complexes of these two transition metals with different recognition motifs, which upon interacting with different inorganic anions, produces desirable quantifiable outputs.
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Dai W, Yu S, Kong C, Zhao D, He C, Liu Z, Dong J, Liu JJ, Cheng F. Effect of electronic structure of energy transfer in bimetallic Ru(II)/Os(II) complexes. Dalton Trans 2023; 52:990-999. [PMID: 36601979 DOI: 10.1039/d2dt03709b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Novel monometallic (μ-LL')Ru, Ru(μ-LL'), homobimetallic Ru(μ-LL')Ru, and heterodimetallic Ru(μ-LL')Os and Os(μ-LL')Ru complexes based on two asymmetrical ligands LL' (where LL' = L1L1', L2L2') have been synthesized and characterized. Spectroscopic analysis indicates that all complexes exhibit intense spin-allowed ligand-centered (LC) transitions at 288 nm and Ru-based moderate spin-allowed MLCT absorption between 440-450 nm. The Ru(μ-LL')Os and Os(μ-LL')Ru dinuclear complexes show Os-based unit absorption in the range of 565-583 nm. The Ru-based units of the complexes present different emission intensities due to differing steric hindrance at the coordination sites of the two bridging ligands. The Os(μ-LL')Ru dinuclear complexes present weaker emission intensity than their parent monometallic complexes (μ-LL')Ru. These results indicate that the emission of Os(μ-LL')Ru dinuclear complexes is quenched by the Os(II)-based units.
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Affiliation(s)
- Weijun Dai
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Shiwen Yu
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Ci Kong
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Defang Zhao
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Chixian He
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Zining Liu
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Jianwei Dong
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Jian-Jun Liu
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
| | - Feixiang Cheng
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing 655011, China.
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Sahoo A, Bhattacharya S, Jana S, Baitalik S. Neural network and decision tree-based machine learning tools to analyse the anion-responsive behaviours of emissive Ru( ii)–terpyridine complexes. Dalton Trans 2023; 52:97-108. [DOI: 10.1039/d2dt03289a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Artificial neural network, adaptive neuro-fuzzy inference and decision tree regression are implemented to analyse the anion-responsive behaviours of emissive Ru(ii)–terpyridine complexes.
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Affiliation(s)
- Anik Sahoo
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Sohini Bhattacharya
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
| | - Subhamoy Jana
- School of Biological Sciences, Indian Association for the Cultivation of Science, Kolkata 700 032, India
| | - Sujoy Baitalik
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata 700032, India
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Deb S, Sahoo A, Mondal P, Baitalik S. Analysis and prediction of anion- and temperature responsive behaviours of luminescent Ru(II)-terpyridine complexes by using Boolean, fuzzy logic, artificial neural network and adapted neuro fuzzy inference models. Dalton Trans 2022; 51:15601-15613. [PMID: 36169624 DOI: 10.1039/d2dt02611b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Anion- and temperature responsive behaviors of three luminescent Ru(II)-terpyridine complexes are utilized here to demonstrate multiple Boolean (BL) and fuzzy logic (FL) operations. Taking advantage of the imidazole NH protons, anion-promoted alteration of the photophysical characteristics of the complexes was thoroughly investigated via absorption, and emission spectral and lifetime measurements. In their free state, the complexes display luminescence representing the "on-state", whereas quenching of luminescence is observed with anions demonstrating the "off-state". Likewise, lowering of temperature induces a substantial increase of luminescence and lifetime demonstrating the "on-state", while the increase of temperature induces a significant decrease of emission intensity and lifetime indicating the "off-state" and the process is reversible in both cases. The complexes thus can act as anion- and temperature-responsive molecular switches. The spectral signatures of the complexes under the influence of anions and temperature were employed to mimic multiple BL and FL functions. Performing very detailed sensing studies by varying the analyte concentration within a wide domain is very tedious, time-consuming and expensive. In order to overcome the lacuna, we implemented machine learning and soft computing tools such as artificial neural networks (ANNs), fuzzy-logic and adaptive neuro-fuzzy inference system (ANFIS) to predict the experimental anion sensing data of the complexes.
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Affiliation(s)
- Sourav Deb
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Anik Sahoo
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Priyam Mondal
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sujoy Baitalik
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
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Kumari M, Dey K, Bera SK, Lahiri GK. Indazole-Derived Mono-/Diruthenium and Heterotrinuclear Complexes: Switchable Binding Mode, Electronic Form, and Anion Sensing Events. Inorg Chem 2022; 61:16122-16140. [PMID: 36149433 DOI: 10.1021/acs.inorgchem.2c02628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The article deals with the newer classes of mononuclear: [(acac)2RuIII(H-Iz)(Iz-)] 1, [(acac)2RuIII(H-Iz)2]ClO4 [1]ClO4/[1']ClO4, and [(bpy)2RuII(H-Iz)(Iz-)]ClO4 [2]ClO4, mixed-valent unsymmetric dinuclear: [(acac)2RuIII(μ-Iz-)2RuII(bpy)2]ClO4 [3]ClO4, and heterotrinuclear: [(acac)2RuIII(μ-Iz-)2MII(μ-Iz-)2RuIII(acac)2] (M = Co:4a, Ni:4b, Cu:4c, and Zn:4d) complexes (H-Iz = indazole, Iz- = indazolate, acac = acetylacetonate, and bpy = 2,2'-bipyridine). Structural characterization of all the aforestated complexes established their molecular identities including varying binding modes (Na and Nb donors and 1H-indazole versus 2H-indazole) of the heterocyclic H-Iz/Iz- in the complexes. Unlike [1']ClO4 containing two NH protons at the backface of H-Iz units, the corresponding [1]ClO4 was found to be unstable due to the deprotonation of its positively charged quaternary nitrogen center, and this resulted in the eventual formation of the parent complex 1. A combination of experimental and density functional theory calculations indicated the redox noninnocent feature of Iz- in the complexes along the redox chain. The absence of intervalence charge transfer transition in the near-infrared region of the (Iz-)2-bridged unsymmetric mixed-valent RuIIIRuII state in [3]ClO4 suggested negligible intramolecular electronic coupling corresponding to a class I setup (Robin and Day classification). Heterotrinuclear complexes (4a-4d) exhibited varying spin configurations due to spin-spin interactions between the terminal Ru(III) ions and the central M(II) ion. Though both [3]ClO4 and 4a-4d displayed ligand (Iz-/Iz•)-based oxidation, reductions were preferentially taken place at the bpy and metal (RuIII/RuII) centers, respectively. Unlike 1 or [2]ClO4 containing one free NH proton at the backface of H-Iz, [1']ClO4 with two H-Iz units could selectively and effectively recognize F-, OAc-, and CN- among the tested anions: F-, OAc-, CN-, Cl-, Br-, I-, SCN-, HSO4-, and Η2PΟ4- in CH3CN via intermolecular NH···anion hydrogen bonding interaction. The difference in the sensing feature between [1']ClO4 and 1/[2]ClO4 could be rationalized by their pKa values of 8.4 and 11.3/10.8, respectively.
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Affiliation(s)
- Maya Kumari
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Krishnendu Dey
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Sudip Kumar Bera
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
| | - Goutam Kumar Lahiri
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai-400076, India
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Sahoo A, Ahmed T, Deb S, Baitalik S. Neuro-Fuzzification Architecture for Modeling of Electrochemical Ion-Sensing Data of Imidazole-Dicarboxylate-Based Ru(II)-Bipyridine Complex. Inorg Chem 2022; 61:10242-10254. [PMID: 35737880 DOI: 10.1021/acs.inorgchem.2c01715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Anion- and pH-sensing behaviors of an imidazole-dicarboxylate-based Ru(II)-bipyridine complex possessing a number of dissociable protons in its secondary coordination sphere are employed here for the creation of multiple Boolean and fuzzy logic systems. The absorption, emission, and electrochemical behaviors of the metalloreceptor were significantly modulated upon the influence of basic anions (such as F-, AcO-, and H2PO4-) as well as by altering the pH of the solution. Interestingly, the deprotonation of the metalloreceptor by selected anions or by alkaline pH, followed by its restoration to its original form by acid or acidic pH is reversible and could be repeated many times. The metalloreceptor is capable to demonstrate several advanced Boolean functions, namely, three-input OR gate, set-reset flip-flop logic, and traffic signal, by employing its electrochemical responses through proper use of different inputs. Administering exhaustive sensing experiments by changing the analyte concentration within a wide range is usually tedious as well as exorbitantly costly. To get rid of these difficulties, we employed here several soft computing approaches such as artificial neural networks (ANN), fuzzy logic systems (FLS), or adaptive neuro-fuzzy inference system (ANFIS) to foresee the experimental sensing data and to appropriately model the protonation-deprotonation behaviors of the metalloreceptor. Reasonably good correlation between the experimental and model output data is also reflected in their tested root-mean-square error values (0.115961 and 0.118894 for the ANFIS model).
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Affiliation(s)
- Anik Sahoo
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India
| | - Toushique Ahmed
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India
| | - Sourav Deb
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India
| | - Sujoy Baitalik
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India
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Toyama M, Hasegawa T, Nagao N. Colorimetric fluoride detection in dimethyl sulfoxide using a heteroleptic ruthenium( ii) complex with amino and amide groups: X-ray crystallographic and spectroscopic analyses. RSC Adv 2022; 12:25227-25239. [PMID: 36199333 PMCID: PMC9450000 DOI: 10.1039/d2ra03593f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 08/19/2022] [Indexed: 11/25/2022] Open
Abstract
A bis-heteroleptic ruthenium(ii) complex, [Ru(Hdpa)2(H2pia)]X2 (1·X2; X = Cl, OTf, or F; Hdpa = di-2-pyridylamine; H2pia = 2-pycolinamide; OTf− = CF3SO3−), was synthesized and spectroscopically and crystallographically characterized. The crystal structures of 1·Cl2·2.5H2O and 1·F2·2EtOH revealed essentially identical geometries for the 12+ dication; however, the dihedral angle between the two pyridyl groups in the Hdpa ligands, which represented the degree of bending of the bent conformation, was affected by hydrogen-bonding interactions between the NH group and counterions. In 1·F2·2EtOH, one of the Hdpa ligands had an unusually smaller dihedral angle (15.8°) than the others (29.9°–35.0°). The two NH groups of each Hdpa ligand and the NH2 group of the H2pia ligand in 12+ acted as receptors for F− anion recognition via hydrogen-bonding interactions in a dimethyl sulfoxide (DMSO) solution, and the reaction showed an unambiguous color change in the visible region. Upon the addition of tetra-n-butylammonium fluoride to the red DMSO solution of 1·(OTf)2·H2O, the solution turned dark brown. 1H NMR analysis and absorption spectroscopy of the reaction between 12+ and the added F− anions revealed that the F− anions did not distinguish between the two amino groups of Hdpa and the amide group of H2pia, although they were in different environments in the DMSO solution. A tris-F-adduct with 12+, 1·F3−, was formed when sufficient F− anions were present in the solution, despite the presence of four NH protons in 12+. Time-dependent DFT calculations of 12+ and 1·F3− were consistent with their absorption spectra. A bis-heteroleptic ruthenium(ii) complex; [Ru(Hdpa)2(H2pia)]X2 (1·X2; X = Cl, OTf, or F; Hdpa = di-2-pyridylamine; H2pia = 2-pycolinamide; OTf– = CF3SO3–) was synthesized and spectroscopically and crystallographically characterized.![]()
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Affiliation(s)
- Mari Toyama
- Department of Engineering Science, Faculty of Engineering, Osaka Electro-Communication University, 18-8 Hatsucho, Neyagawa, Osaka, 572-8530, Japan
- Department of Chemistry of Functional Molecules, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada, Kobe, Hyogo, 658-8501, Japan
- Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama, Kawasaki, Kanagawa, 214-8571, Japan
| | - Tomoki Hasegawa
- Department of Chemistry of Functional Molecules, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Higashinada, Kobe, Hyogo, 658-8501, Japan
| | - Noriharu Nagao
- Department of Applied Chemistry, School of Science and Technology, Meiji University, 1-1-1 Higashimita, Tama, Kawasaki, Kanagawa, 214-8571, Japan
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Feng R, Yu X, Autschbach J. Spin-Orbit Natural Transition Orbitals and Spin-Forbidden Transitions. J Chem Theory Comput 2021; 17:7531-7544. [PMID: 34792327 DOI: 10.1021/acs.jctc.1c00776] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Natural transition orbitals (NTOs) are in widespread use for visualizing and analyzing electronic transitions. The present work introduces the analysis of formally spin-forbidden transitions with the help of complex-valued spin-orbit (SO) NTOs. The analysis specifically focuses on the components in such transitions that cause their intensity to be nonzero because of SO coupling. Transition properties such as transition dipole moments are partitioned into SO-NTO hole-particle pairs, such that contributions to the intensity from specific occupied and unoccupied orbitals are obtained. The method has been implemented within the restricted active space (RAS) self-consistent field wave function theory framework, with SO coupling treated by RAS state interaction. SO-NTOs have a broad range of potential applications, which is illustrated by the T2-S1 state mixing in pyrazine, spin-forbidden versus spin-allowed 4f-5d transitions in the Tb3+ ion, and the phosphorescence of tris(2-phenylpyridine) iridium [Ir(ppy)3].
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Affiliation(s)
- Rulin Feng
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Xiaojuan Yu
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
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Deb S, Sahoo A, Ahmed T, Baitalik S. Stimuli-Responsive Molecular Switches and Logic Devices Based on Ru(II)-Terpyridyl-Imidazole Coordination Motif. J Phys Chem B 2021; 125:8919-8931. [PMID: 34323072 DOI: 10.1021/acs.jpcb.1c05305] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report herein the synthesis, photophysics, and electrochemistry of three Ru(II)-terpyridine complexes derived from a new terpyridyl-imidazole ligand (tpy-HImzPh3F2) and study their pH- and temperature-responsive behaviors toward the fabrication of molecular switches. The complexes emitted at room temperature (RT) have a lifetime within the 4.5-49.0 ns domain, depending on the auxiliary ligand and the solvent used. In the acidic region, the complexes exhibit emission, indicating the "on-state", while in the basic condition, the emission is totally quenched, indicating the "off-state". Similarly, when the temperature is lowered, the emission intensity and lifetime are enhanced, demonstrating the on-state, while increase of temperature leads to quenching of the emission intensity and lifetime, designated as the off-state. In both cases, the process is reversible. The bathochromic shift of the spectral band together with the emission quenching and lowering of the Ru3+/Ru2+ potential is also observed upon deprotonation at elevated pH. In addition, systematic variation of the absorption spectral behaviors upon variation of pH helps in evaluation of the pKa's of the complexes. In essence, the complexes can act as switches emanated from a huge change in their absorption, emission, and redox behaviors as a function of their acidity/basicity (pH) and temperature. Moreover, their emission spectral responses as a function of pH and temperature were utilized for the fabrication of two-input binary logic gates. Density-functional theory (DFT) and time-dependent density-functional theory (TD-DFT) computations are performed for appropriate interpretation of the spectral bands.
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Affiliation(s)
- Sourav Deb
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700 032, India
| | - Anik Sahoo
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700 032, India
| | - Toushique Ahmed
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700 032, India
| | - Sujoy Baitalik
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700 032, India
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