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•Monometallic heteroleptic complexes of Dy(III) with general formula Dy(Hfodo)3L have been synthesized.•The prepared complexes have been investigated by thermal, spectroscopical and ...electrochemical studies.•Electronic and optical band gap has found to be quite similar and in the range of conducting region.•Yellow luminescence is observed corresponding to 4F9/2→6H13/2 transition which demonstrates the utility of complexes in generation of high-efficiency organic light emitting materials.
A series of ternary complexes of dysprosium tris-β-diketonate was prepared by using phenanthroline and its substituted derivatives as neutral ligands. The complex formation or the coordination mode of organic moieties was analysed by elemental, infrared, proton NMR and UV–Visible analyses. The anhydrous nature of prepared complexes was illustrated by using thermogravimetric and infrared studies. The band gap was also measured which is present in the range of conducting zone. The luminescence characteristics were measured in solid and solution. The complex upon excitation under UV light generates emission in the yellow region which indicates proficient energy transference from coordinated moieties to the central Dy(III) ion. The correlated color temperature (CCT) of Dy(III) complexes has been calculated and found to be ∼ 5000 K which belongs to a cold light region. The contribution of 4F9/2 → 6H13/2 transition (75 %) is highest towards total radiative processes and it might be regarded as an acceptable transition for laser amplification. The prepared complexes of Dy(III) could be utilized in fabricating OLEDs and displays due to their band gap value, large thermal stability and high luminous characteristics.
Dysprosium (Dy3+) containing four single-molecule complexes with 1,3-diketone ligand, TFPB (4,4,4-trifluoro-1-phenyl-1,3-butadionate) along with neutral co-ligands of varying denticity were ...synthesized and two of them were explored as potential sources of near-white light emission. The choice of ligand as well as the coordination surroundings of Dy(III) ion significantly influence the blue (B: 4F9/2 → 6H15/2) and yellow (Y: 4F9/2 → 6H13/2) emissions. The inclusion of the auxiliary ligand such as topo in D1 leads to reduction in emission intensity compared to D2-D4 due to less effective sensitization. At room temperature, the CIE color coordinates for complexes D1 and D4 approach the coordinates of perfectly balanced and idealized white light (0.333, 0.333). Furthermore, Correlated Color Temperature (CCT) values for D1 and D4 characterize them as cold-white-light emitters, while the complexes D2 and D3 are categorized as a neutral-light emitter. In addition to their visible emissions, the semi-conducting properties and suitable deactivation lifetime corresponding to these synthesized complexes (D1-D4) have also been extensively studied and found potential applications in basic research, security printing, sensors, detectors and OLEDs.
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•Synthesized luminescent dysprosium complexes incorporating 1,3-diketone and neutral ligands.•Investigated PL emission spectra for understanding their near-white and yellow emission.•Quantified the complex's color in terms of CIE 1931 color space with measurement of the intensity of color.•Compared photoluminescent properties of complexes on the basis of denticity of coordinating moieties.
The set of four ternary coordination compounds of terbium were prepared with diketone 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione (TFDH) and four different neutral ligands (L) having formula ...Tb(TFDH)3L. Resulting compounds were characterized using different techniques including NUV absorption studies, photoluminescence (PL) spectroscopy, electrochemical and thermal analyses. PL spectra confirmed the green luminescence of synthesized complexes by exhibiting characteristic dominant 5D4 → 7F5 peak around 545 nm. Electronic and optical energy gap values lying at ∼3.5 eV reveals their potential to use in semiconductor materials. All the spectral results are in good agreement with each other and highlight their utility in lighting, biomedical imaging and sensors etc.
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•Ternary Tb(III) complexes were prepared using β-diketone and 1,10-phenanthroline based neutral ligands.•NMR spectra exhibited dipolar shift due to the paramagnetic nature of terbium ion.•The optical band gap and the electronic band gap lie within the semiconductor range.•5D4.→ 7F5 MD transition is responsible for the green luminescence in the synthesized complexes.
•Coordination sphere effects: Spectroscopic analysis of samarium β-diketonate complexes.•Emission peak at 648 nm: Electric dipole transition responsible for characteristic orange-red ...emission.•Spectroscopic evidence confirms octacoordinated samarium ion with carbonyl oxygen and nitrogen coordination.•Semiconducting properties and good thermal stability suggested display applications.
Ternary Sm(III) complexes of general representation Sm(TFDH)3L were synthesized to understand influence of different auxiliary moieties on their optoelectronic properties. The synthesized complexes were thoroughly investigated using elemental, IR, NMR, UV and PL studies. In these complexes, the emitting metal ion is bonded with six O atoms from di-ketone 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione and two nitrogen atoms from neutral ligand i.e. 1,10-phenanthroline and its derivatives. Proton NMR spectral data showed that samarium ion induced chemical shift is dipolar in nature. The photoluminescence analysis showed that the complexes show intense orange-red emission due to 4G5/2 → 6H9/2 transition. Moreover, CIE color coordinates supported the results obtained from photoluminescence study, providing additional confirmation of the luminescent properties of prepared complexes within the orange-red region. Their utility in displays and OLED's was confirmed by studying their optical and electronic band gaps.
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•Synthesized samarium-centered ternary complexes incorporating ‘TFPB’ & various neutral moieties having different denticities.•Explored the vibrational modes in the IR spectra to identify ligand ...coordination and discussed the changes in IR spectra upon complex formation.•Studied photoluminescence spectra and energy transfer phenomenon to understand the influence of different coligands on the luminescence intensity.•Most intense transition at around 648 nm as a consequence of ΔJ = 2 transition, indicates the pronounced asymmetry in the chelation environment surrounding the central ion.•The synthesized complexes display conductive properties, a notably extended luminescent lifespan and color space parameters in orange-red region, indicating their potential utility in photonic devices.
The synthesis and characterization of four octacoordinated complexes of Sm(TFPB)3 with different neutral ligands have been successfully performed. This study aimed to evaluate the potential of neutral ligands in enhancing the emission intensity of Sm(III) ion by investigating their light-emitting characteristics. Dominance of hypersensitive transition 4G5/2 → 6H9/2 is observed which suggests the asymmetry in the vicinity of Sm(III) ion in these complexes, reinforced by asymmetry ratio. Stark-splitting in the magnetic dipole 4G5/2→6H5/2 transition was consistent across most complexes, but Sm(TFPB)3(topo)2 displayed a different pattern due to monodentate auxiliary moiety, which does not provide as much structural rigidity and stability as found in the other complexes. Various analyses including IR, NMR, CV, TGA, UV and colorimetry, supported possible applications of synthesized complexes in devices based on photonics, sensors, magnets and other technological fields.
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Four terbium(III) ternary complexes, namely Tb(TFPB)
3
(topo)
2
(N1), Tb(TFPB)
3
(bipy) (N2), Tb(TFPB)
3
(phenan) (N3) and Tb(TFPB)
3
(neocup) (N4), comprising ...4,4,4-trifluoro-1-phenyl-1,3-butanedione (TFPB) and nitrogen and oxygen donors, have been successfully synthesized and subjected to detailed structural characterization. The analyses include elemental analysis, FTIR spectroscopy, thermogravimetric studies and
1
H-NMR spectroscopy. IR studies presented vibrational peaks in 1470 to 1500 cm
−1
region which are characteristic feature of the complexation of Ln(III) ion to 1,3-diketones. NMR analysis presented high dipolar paramagnetic shift from 114.7 to − 199.0 ppm due to TFPB and neutral ligand, respectively. Band gap values suggest the potential use of these complexes in semiconductor devices. The photoluminescent properties of these complexes have been examined in their solid states, revealing the impact of neutral ligands on the photoluminescent properties of Tb(III) ion. A thorough investigation into the energy transfer process is undertaken, establishing correlation between luminescence of the acceptor (terbium(III) ion) and the triplet state energy of the donor (ligands). Out of the set of complexes under examination, the luminescence intensity from complex N2 stands out as the most intense, followed by N4, N3 and N1. Additionally, the CIE color space coordinates for these complexes are precisely calculated and presented. Beyond their visible green emission, thermal patterns associated with these synthesized complexes have also been comprehensively explored.
In this study, β-diketone (1,1,1-trifluoroacetylacetone, tfaa) based mononuclear anhydrous octacoordinated dysprosium complexes i.e. Dy(tfaa)3(TOPO)2 (D1), Dy(tfaa)3(phen) (D2), Dy(tfaa)3(NeoC) (D3) ...and Dy(tfaa)3(BathoC) (D4) were synthesized using four different neutral ligands. The effect of different sensitizers on Dy(III) ion is analyzed using various spectroscopic and analytical techniques. The composition and bonding were examined by elemental analysis, infrared spectroscopy, NMR spectroscopy and thermal analysis (TGA). The luminescent characteristics of the synthesized complexes were further investigated. The complexes, when exposed to UV light, displayed characteristic emissions of the central Dy(III) ion. The photoluminescence spectra indicated the strongest emission intensity of D3 complex. The hyper-intense transition in all complexes is sensitive to the metal ion environment. The semiconducting nature of complexes was confirmed by optical and electronic band gap values obtained from absorption spectroscopy and cyclic voltammetric analysis, respectively. The neutral ligands (TOPO, phen and its derivatives) along with tfaa, are found to be good sensitizers for trivalent dysprosium ion. All the characteristic features of these prepared complexes show their potential applications in the fabrication of OLEDs.
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•Ternary Dy-tfaa complexes were synthesized by employing monodentate & bidentate as ancillary ligand.•The mechanism of energy transfer demonstrates the efficient sensitization of Dy(III) ion occurs via photosensitizing ligands.•The hypersensitive electric dipole peak noticeable at around 575 nm due to 4F9/2 → 6H13/2 transition is responsible for the yellow emission.•Cyclic voltammetric and Tauc's analyses were conducted to study the redox behavior, electronic band gap and optical band gap, respectively.
•Synthesized dysprosium (III) complexes by utilizing TFDH with 2,2ʹ-bipyridyl and its derivatives.•FTIR and NMR confirmed coordination via oxygen and nitrogen donor atoms in ternary ...complexes.•Semiconducting behavior of complexes confirmed by optical and CV band gap values.•High luminescence lifetimes suggested applications in display devices.
The ternary dysprosium complexes involving 1,1,1-trifluoro 5,5-dimethyl 2,4-hexanedione (TFDH) along with 2,2ʹ-bipyridyl and its derivatives have been synthesized. Elemental, infrared and proton NMR analyses were used to evaluate the bonding patterns between dysprosium ion and organic moieties. UV–Visible and photoluminescence spectroscopy were used to examine the optical characteristics. To confirm the anhydrous nature of synthesized complexes, IR and thermogravimetric data were utilized. The band gap value lies in semi-conducting region was explained by Tauc's plot and CV curve, respectively. The photophysical characteristics of dysprosium complexes have been studied in powdered form. The appearance of yellow luminescence on irradiation under NUV-light indicates a highly efficient transfer of energy mechanism from organic ligand to the Dy(III) ion. The CCT values were found to be suitable for cold light sources. The ∆J = 2 transition dominates the overall emission spectra with branching ratio ∼70% is ideal for laser reinforcement. The synthesized Dy(III) complexes possess band gap in semi-conducting range, good thermal stability and high luminous properties, which makes them suitable for applications in displays and lighting technologies.
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Background: It is estimated that around 120 million people in tropical and subtropical areas of the world are infected by filariasis. In the Southeast and South Asian regions, Wuchereria bancrofti is ...the most prevalent parasite,causing filariasis in 99.4% of cases. We report a rare case of amyloidosis kidney with an incidental finding of microfilariae. Case report: An 85 year old male presented with complaints of gradually progressive anasarca and loss of weight for 2 months as well as vomiting and decreased urine output for a week. On clinical examination, aside from mild pallor, there was evidence of bilateral pitting pedal edema and free fluid in the abdomen. Sonography revealed the presence of bilateral renal parenchymal disease and bilateral hydrocele with thickened spermatic cord. Lower lobe consolidation was the only significant finding on the chest skiagram. The patient was rigorously worked up to identify pathology in other systems, but all the data were within normal limits. Histopathological examination of the renal biopsy specimen revealed complete to partial replacement of most of the glomeruli by pink, hyaline eosinophilic material and microfilariae of Wuchereria bancrofti were seen incidentally. Blood vessels showed pink hyaline material in their walls. Tubules and interstitium were unremarkable. The provisional diagnosis of amyloidosis kidney was confirmed by positivity on methyl violet staining. Conclusion: In the present case, the clinical picture did not provide any clue regarding the association of amyloidosis kidney with filariasis except for mild peripheral eosinophilia. However, renal biopsy revealed amyloidosis with microfilariae of Wuchereria Bancrofti. It is presumed that, in this case, microfilariae entered the glomerular capillaries after breaching the blood renal barrier. This is the first case in which renal amyloidosis was shown to be associated with microfilariae of Wuchereria bancrofti. The possibility of the latter condition, resulting in the genesis or development of the former, needs to be further investigated and discussed.
There have been multiple incidents where doctors have been assaulted by patient relatives and hospital facilities have been vandalized. This has led to mass agitations by Physicians across India. ...Violence and vandalism against health-care workers (HCWs) is one of the biggest public health and patient care challenge in India. The sheer intensity of emotional hijack and the stress levels in both practicing HCWs and patient relative's needs immediate and detail attention. The suffering of HCWs who are hurt, the damage to hospital facilities and the reactionary agitation which affects patients who need care are all together doing everything to damage the delivery of health care and relationship between a doctor and a patient. This is detrimental to India where illnesses and Injuries continue to be the biggest challenge to its growth curve. The expert group set by The Academic College of Emergency Experts and The Academy of Family Physicians of India makes an effort to study this Public Health and Patient Care Challenge and provide recommendations to solve it.
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