Role of energy transfer, defect, and lattice dimension in photophysical characteristics of AWO 4 :Nd 3+ (A=Ca, Sr and Ba)

2020 ◽  
Vol 103 (9) ◽  
pp. 5098-5110
Author(s):  
Chandra S. Datrik ◽  
Kathi Sudarshan ◽  
Santosh K. Gupta ◽  
Purnananda Nandi
2011 ◽  
Vol 35 (1) ◽  
pp. 15-27
Author(s):  
Zoran Ivić ◽  
Željko Pržulj

Adiabatic large polarons in anisotropic molecular crystals We study the large polaron whose motion is confined to a single chain in a system composed of the collection of parallel molecular chains embedded in threedimensional lattice. It is found that the interchain coupling has a significant impact on the large polaron characteristics. In particular, its radius is quite larger while its effective mass is considerably lighter than that estimated within the one-dimensional models. We believe that our findings should be taken into account for the proper understanding of the possible role of large polarons in the charge and energy transfer in quasi-one-dimensional substances.


2020 ◽  
Vol 153 (11) ◽  
pp. 114302
Author(s):  
Diletta Meroni ◽  
Angelo Monguzzi ◽  
Francesco Meinardi

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Stefan Lis ◽  
Krzysztof Staninski ◽  
Tomasz Grzyb

The europium (III) complex of coumarin-3-carboxylic acid (C3CA) has been prepared and characterized on the basis of elemental analysis, IR, and emission (photoluminescence and electrochemiluminescence) spectroscopy. The synthesised complex having a formula Eu was photophysically characterized in solution and in the solid state. Electrochemiluminescence, ECL, of the system containing the Eu(III)/C3CA complex was studied using an oxide-covered aluminium electrode. The goal of these studies was to show the possibility of the use of electrochemical excitation of the Eu(III) ion in aqueous solution for emission generation. The generated ECL emission was very weak, and therefore its measurements and spectral analysis were carried out with the use of cut-off filters method. The studies proved a predominate role of the ligand-to-metal energy transfer (LMET) in the generated ECL.


Author(s):  
Shaunak M. Shaikh ◽  
Stefan Ilic ◽  
Bradley J. Gibbons ◽  
Xiaozhou Yang ◽  
Elena Jakubikova ◽  
...  

2017 ◽  
Vol 19 (34) ◽  
pp. 23194-23203 ◽  
Author(s):  
Debashis Majhi ◽  
Moloy Sarkar

With the aim to understand the role of the ionic constituents of ionic liquids (ILs) in their structural organization, resonance energy transfer (RET) studies between ionic liquids (donor) and rhodamine 6G (acceptor) have been investigated.


1992 ◽  
Vol 47 (12) ◽  
pp. 1764-1774 ◽  
Author(s):  
Karl-Dietrich Gundermann ◽  
Elke Romahn ◽  
Maximilian Zander

9,10-Di(1-naphthyl)phenanthrene (5 a) and 9,10-di(2-naphthyl)phenanthrene (5 b) have been synthesized. It is shown that 5 a and 5b both form two stable rotational (cis/trans) isomers with the naphthalene molecular planes perpendicular to the phenanthrene plane. In the case of 5 a the mixture of the two isomers has been separated in a preparative scale and each isomer characterized by e. g., NMR spectroscopy. Photocyclization of 5a leads to benzo[e]phenanthro[1,2,3,4-ghi]perylene (9) while 5 b yields phenanthro[9,10-i]pentahelicene (14); both hydrocarbons have not been previously described in the literature. The observed selectivities of photocyclization are explained on the basis of the structures and stabilities of the initially formed photoproducts (dihydro structures 15 and 14 a). The role of intramolecular non-radiative singlet-singlet energy transfer (naphthalene → phenanthrene) as competing with photocyclization is discussed in detail.


2017 ◽  
Vol 50 (3) ◽  
pp. 787-794 ◽  
Author(s):  
Swati Bishnoi ◽  
G. Swati ◽  
Paramjeet Singh ◽  
V. V. Jaiswal ◽  
Mukesh K. Sahu ◽  
...  

This paper reports the detailed synthesis mechanism and the structural, morphological and optical characterization of ultraviolet (∼311 nm) excitable samarium doped gadolinium yttrium orthovanadate, (Gd,Y)VO4:Sm3+, nanocrystals. X-ray diffraction and Rietveld refinement studies confirmed that the synthesized samples crystallize in a tetragonal structure withI41/amdspace group. The enhanced photoluminescence intensity of (Gd,Y)VO4:Sm3+compared with the existing YVO4:Sm3+phosphor clearly indicates the significant role of Gd3+ions. This has been attributed to the sensitization of the6PJenergy level of Gd3+ions by energy transfer from orthovanadate (VO43−) ions and subsequent energy trapping by Sm3+ions. The energy transfer from VO43−to Sm3+viaGd3+ions as intermediates and concentration quenching of Gd3+luminescence are discussed in detail. The optical band gap of the as-prepared nanocrystals has been estimated using UV–vis–NIR absorption spectroscopy, which reveals a slightly higher band gap (3.75 eV) for YVO4as compared to GdYVO4(3.50 eV). Furthermore, confocal microcopy, decay parameters and Commission Internationale de l'Eclairage chromatic coordinates have supplemented these studies, which established the suitability of these nanophosphors for achieving spectral conversion in silicon solar cells.


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