Research Journal of Chemical Sciences ______________________________________________ ISSN 2231-606X Vol. 3(4), 84-86, April (2013) Res. J. Chem. Sci. International Science Congress Association 84 Short Communication Spectroscopic study of Inner Transition metal Mn2+ ion in CeSOCl PhosphorGedam S.C. K.Z.S. Science College Kalmeshwar, Nagpur 441501, INDIAAvailable online at: www.isca.in Received 18th February 2013, revised 25th February 2013, accepted 16th March 2013Abstract CeSOCl: Mn phosphor is prepared by wet chemical method. The spectroscopic study and electronic states of Mn2+ are derived from excitation spectra for greenemitting CeSOCl: Mn phosphor and is found to give a spectrum consistent with linear symmetry in increasing intensity of Mn2+ ion. Mn2+ emission at 535 nm was observed in the present host due to transition. The emission spectra shows single peak having sharp shape and strong intensity at 535 nm. It can be used as a green phosphor. Keywords: Inorganic material, wet chemical, photoluminescence, lamp phosphor, Transition metal. Introduction The luminescence properties of divalent manganese have been studied intensively and are used in many luminescent materials. Transition metal ions have an incompletely filled d-shell i.e. their electron configuration is dn (0 n 10). The energy levels originating from such a configuration have been calculated by Tanabe and Sugano, taking the mutual interaction between the d-electron as well as the crystal field into account. The example is the d configuration, of which Mn2+, used in many luminescent materials, is a well-known representative. In fact the Mn2+ ion is practically colorless. However, Mn2+compounds, like MnF and MnCl, have a high rose colour. The presence of a transition metal (TM) impurity in an insulating material leads to the appearance of physicochemical properties which are absent in the pure host lattice and may be useful for applied devices such as solid-state lasers, storage phosphors, etc. Despite a doped material being certainly more complex than a pure one. Mn2+ has the 3d configuration and from the Tanabe-Sugano diagram it follows that the ground level is . Emission arises from the (G) level, which shifts to lower energies for higher crystal field strengths. All optical absorption transitions are parity and spin forbidden. Generally, Mn2+-activated phosphors are divided into two classes: those with green emission and those with orange-to-red emission. In octahedral surroundings with large crystal field the emission is usually red; in tetrahedral surroundings with a much smaller crystal field the emission is usually green. A well-known example belonging to the latter class is ZnGa: Mn2+. Another possibility to obtain a green Mn2+ emission is to choose a lattice in which Mn2+ is on a site, which is considerably larger than the Mn2+ radius. This requirement is met in compounds like SrB10: Mn2+ in which the Mn2+ emission is at 512 nm. Also GdF:Mn2+ offers a large site for Mn2+. If the Mn2+ ion is positioned on a regular Gd3+ site, it is surrounded by eight F- ions. The F- coordination resembles that of a twisted cube. Lammer and Blasse reported for GdF: Mn2+ emission with a maximum at 520 nm. Rare earth impurity ions was extensively studied because of its high sensitivity and its ability to store the incident energy5,6giving it suitability for radiation dosimetry. The material has been marketed as a commercial TL dosimeter, CaF: Eu, under the commercial name TLD-200. On the other hand, luminescence studies of SrF and BaF7-10 doped with rare earths has received much less attention, despite their intense luminescence. For BaF Lucas and Kapsar11 studied the luminescence properties of BaF: Eu and the possibility of using this material in radiation measurements. CaF: Mn does not give any fluorescence under the UV excitation while CaF: Ce gives a characteristic Ce3+ fluorescence emission with UV light excitation .The combination of Ce, Mn in the CaF lattice however gives brilliant Mn2+ fluorescence emission in addition to that of Ce3+ on UV excitation due to energy transfer from Ce3+ to Mn2+ ions. Material and MethodsCeSOCl (pure); and CeSOCl: Mn phosphors were prepared by a wet chemical method. CeCl and Ce(SO3 of analar grade were taken in a stoichimetric ratio and dissolved separately in double distilled de-ionized water, resulting in a solution of CeSOCl (equation 1). Water-soluble sulphate salt of manganese was then added to the solution to obtain CeSOCl: Mn. Confirming that no undissolved constituents were left behind and all the salts had completely dissolved in water and thus reacted. CeCl3 + Ce(SO3 3CeSOCl (1) Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 84-86, April (2013) Res. J. Chem. Sci. International Science Congress Association 85 The compounds CeSOCl (pure) and CeSOCl: Mn in its powder form was obtained by evaporating on 80 c for 8 hours. The dried samples were then slowly cooled at room temperature. The resultant polycrystalline mass was crushed to fine particle in a crucible. The powder was used in further study. Formation of the compound was confirmed by taking the x-ray diffraction (XRD) pattern that matched with the standard data available. Formation of the compound was confirmed by taking the x-ray diffraction (XRD) pattern. The photoluminescence (PL) emission spectra of the samples were recorded using Fluorescence spectrometer (Hitachi F-4000). The same amount of sample was used in each case. Emission and excitation spectra were recorded using a spectral slit width of 1.5 nm. Results and DiscussionPhotoluminescence (PL) in CeSOCl: Mn: Transition metal ions have been widely used in luminescent materials, e.g., Mn2+, a transition metal center, has been doped into more than 500 inorganic hosts12 for luminescence with emission range from 490 to 750 nm. According to reports, the 3d multiplet energies of Mn2+ in crystals depend largely on the covalency interaction with the host crystal or the crystal field, because the 3d electrons of the transition metal ions are the outermost electrons. The tetrahedral coordinated Mn2+ ion gives a green emission, while the octahedral coordinated Mn2+ ion exhibits an orange-to-red emission13 Mn2+ emission at 535 nm was observed in the present host due to 1 1 transition. This corresponds to blue-green part of the visible spectrum. An excitation spectrum is peaking at 254 nm wavelength whereas Ce3+ contained in a host peaking an emission at 310 nm due to 5d 4f transition as shown in figure-2. Figure-3shows emission spectrum with various contents of Mn2+ ions. In the figure the excitation spectrum (monitoring at 535 nm emission) has intense broad bands with maxima at 235 nm. Selecting 235 nm excitation wavelength, it was recorded the emission spectra for Mn doped ions in CeSOCl host. The curves a, b, c, d, and e show the emission spectra for the same host with Mn a) 1, b) 0.5, c) 0.3, d ) 0.2, and e) 0.1 mol.%, concentrations respectively. The emission spectra shows single peak having sharp shape and strong intensity at 535 nm (green emission). Figure-4 showsschematic Mn2+energy level diagram in CeSOCl host in which 535 nm emissions comes from 1 to 1 ground state excited at 254 nm. Conclusion The primary objective to present this paper is the development and implementation of inexpensive CeSOCl: Mn green emitting material for photoluminescence study. Mn2+ emission at 535 nm was observed at green region in the present host due to 1 1 transition excited at 254 nm. Here we report an investigation of CeSOCl: Mn material which have very low toxicity and cost, and can be prepared in open air atmosphere using simple wet chemical method. The CeSOCl: Mn phosphor may be used as a lamp phosphor. Figure-1 XRD Pattern of CeSOCl Figure-2 PL excitation spectrum (exc = 254 nm) of CeSOCl: Mn 0.1 mole% Figure-3 PL emission spectra (emi =535 nm) of CeSOCl: Mn a) 1, b) 0.5, c) 0.3, d ) 0.2, e) 0.1 mol.% Research Journal of Chemical Sciences ___________________________________________________________ ISSN 2231-606XVol. 3(4), 84-86, April (2013) Res. J. Chem. Sci. International Science Congress Association 86 Figure-4 Schematic Mn2+energy level system in CeSOCl Acknowledgements Author is thankful to University Grant Commission (UGC), New Delhi Government of India, for the financial support. References1.Blasse G. and Grabmaier B.C., Luminescent Materials. Springer-Verlag, Berlin, 232, (1994)2.Koskentalo T., Leskela M. and Niinisto L., Mater.Res.Bull., 20, 265-271 (1985)3.Wyckoff R.W.G., Crystal Structures, 2(2), edn.Wiley, New York (1964)4.Lammers M.J.J, and Blasse G., Nanotechnology Applications for Clean Water, Phys.Status Solidi (b), 127,663-669 (1985)5.Sunta C., A review of thermoluminescence of calcium fluoride, calcium sulphate and calcium carbonate, Radiat. Prot. 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