The Infra Red spectra of phosphor materials BaSO4 and CaS04 doped with rare earth material Dy. by Prof K L Narayana

trusciencetrutechnology@blogspot.com

Volume 2013, Issue No.9,Dt. 3 September 2013:Time: 10h29m.AM.

The Infra Red spectra of phosphor materials BaSO₄  and  CaS0₄ doped with rare earth material Dy.

by

Professor Dr Kotcherlakota Lakshmi Narayana,

{Retd. Prof.of Physics, SU, Kolhapur} 17-11-10, Narasimha Ashram,

Official Colony, Maharanipeta.P.O. Visakhapatnam -530002,

Mobile No. 9491902867 and; 9542717723

Key Words: compositions, BaSO₄ and CaSO₄, Dy dopant,

Gamma irradiation.

A B S T R A C T

                       

               The Infra Red spectra of phosphor materials BaSO₄  and CaS0₄  doped with rare earth material Dy at different percentages and compositions are obtained, by the author, following the spirit of initial investigations made by Prof. K. R. Rao,  mentioned in his D. Sc. Thesis Madras University made during the years 1919-1924 at Vijayanagaram. In Dy spectrum, emission lines at 475nm, 574nm are most intense. Tb and Dy are most effective activators out of selected six rare-earths and to some extent Sm are good for obtaining the TL spectrum in Ca₂Mg(BO₃)₂.  Dy dopant is essentially trivalent. Glow Peaks in TL glow curves gamma irradiated 6.5E+03R Calcium Magnesium Borate Phosphors with different dopants. The data of emission for Dy rare earth doping phosphors is given explicitly. The Infra Red Spectra reported constitutes a first report of its kind by the author of about 10 Phosphor Solid Samples.

                             

                   Prof  K R Rao D.Sc. (Madras). D.Sc(London) receiving           the IR spectrometer at Andhra University, during the year 1961-1962 when the present author was a J R F in C S I R Scheme.
Refer below.

DETAILS  

          The phosphors investigated, by me, at Shivaji University, Kolhapur - 416004 are enlisted below.

1        1.  BaSO₄             : Mn 5% : Dy 0.5%   

2        2.  BaSO₄           : Mn 2%: Dy 0.5%

3        3.  Ba x SO₄: Mn(1-x)  : Dy    x=0.2

4        4.  Ba x SO₄: Mn(1-x)  : Dy    x=0.5

5        5.  Ba x SO₄: Mn(1-x)  : Dy    x=0.1

6        6.  Ca x: SO₄ (1-x)        : Dy    x=0.2

7        7.  Ca x: SO₄ (1-x)        : Dy    x=0.4

8        8.  Ca x: SO₄ (1-x)        : Dy    x=0.6

9        9.  Ca x: SO₄ (1-x)        : Dy    x=0.8

1       10.           CaSO₄             : Dy  100%: 0.5%

      Skip 7 similar to 6 scan and as well 4.

    The phosphor material exhibits the Infra Red Spectra record and the data is reported for the samples listed as sample No. 1, next Nos. 3, 2 with 4 skipped, next Nos.5, 6 and 8 with 7 and 9 skipped and finally 10.

Dy Dopant Rare Earth

    With my Ph. D. student (Late Mr. Dhayagude) at Shivaji University,  I have investigated the rare earth Dy dopant for its Thermoluminescence Characteristics in the matrix of Ca₂Mg(BO₃)₂ lattice in n.m units.

Data                   EARLIER   UNASSIGNED PRESENT(nm)

Oà 6H _15/2              -             339.0

     L1                           364.0

     L2                           416.6

     L3                           461.4

------------------------------------------------------

4F_9/2 à 6H_15/2           474.9     

   (6H_11/2 à 6H_15/2 )   479.6  

4F_9/2 à 6H_15/2                         502.3              

                                                539.0

L4                              557.5

L5                              568.0

L6                              570.0

------------------------------------------------------

4F_9/2 à 6H_13/2                       -

I4                            574     618.0

L5                             -          -

-------------------------------------------------------

4F_9/2 à 6H_11/2             657.4     -

            I6                    667.7

----------------------------------------------------

  4F_9/2 à 6H_9/2                -        742.0

            “                         -        742.9

----------------------------------------------------

Page 185: Ph.D thesis submitted to  Shivaji University,
by  Late Dhayagude under the author in July 1984

   

In Dy spectrum, emission lines at 475nm, 574nm are most intense. Tb and Dy are most effective activators out of selected six rare-earths and to some extent Sm are good for obtaining the TL spectrum in Ca₂Mg(BO₃)₂.  The Dy dopant is essentially trivalent.   

Glow Peaks in TL glow curves gamma irradiated 6.5E+03R Calcium Magnesium Borate Phosphors with different dopants. The data for Dy is as follows:

--------------------------------------------------------------------------------------------------------

Sample Dy    Dopant              Glow Peak Intensities in units of `1E-07

                    Concentration %  150 ⁰C   180⁰C   280⁰C   375⁰C

--------------------------------------------------------------------------------------------------------

D28              0.2                              -              5.7   -       10

D29              0.5                              -              4.0   3.3   9

D30              1.0                             1.5           1.9   1.2   3.0

--------------------------------------------------------------------------------------------------------

    (p.107 reference)   

         

Main feature is most intense peak at 400⁰C in case, of dopant Dy, in other samples it was less weak. Dy replaces Ca position in Ca₂Mg(BO₃)₂ and gives sensitive phosphors. Dy atomic number is 66 and ionic radius is 1.07Å.  


GLOW PEAKS   

             Fig.F The Emmission spectrum of rare-earths
                          in Ca2Mg(BO3)2.  Photo0764    

        
                          Fig.G TL glow curve 
            after 6E+04 gamma irradiation Photo0765

CONCLUSIONS

    

            The phosphor material exhibits the Infra Red Spectra record and the data is reported for the samples listed as sample No. 1, next Nos. 3, 2 with 4 skipped, next Nos. 5, 6 and 8 with 7 and 9 skipped and finally No.10. Extensive data on Dy doped phosphor materials is reported herein with the object of analyzing importance of it in Thermoluminescence studies.

Special Thanks
                
       I am to thank the Vice-Chancellors of Shivaji University, Kolhapur, 416004 Viz., Barrister P. G. Patil, Shri Kanbarkar and Prof Bhogisayanam who have taken keen interest in my work and academic promotions. I was appointed during A G Pawar  regime and Mrs Ithappe in 1966 on June 1st.

PHOTOS AND DATA

                                Fig.1 IMG_1092 graph 1 

                                      
                           Fig.5  IMG_1099   graph 1

                      Fig.2 IMG_1093 graph 3 and 2 skip 4 

                            
                 Fig. 6 IMG_1098 graph 3 and 2 skip 4   

                          

               Fig.3 IMG_1094  graph 8, 6 and 5 skip 7 similar to 6 

                       Fig. 7 IMG_1095 data of samples 5 6 8 

                    
                            Fig.4 IMG_1096 no 10 graph            
                        

                          

                                Fig.8 IMG_1097  graph 10      

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    ADDENDUM

Special Note: 
                It is unfortunate the work carried out and reported in the D.Sc. Thesis of Madras University, was willfully neglected by the committee of Nobel Prize experts, during Prof K. R. Rao, stay in England in   years 1927-1930, and that led to an unprecedented chaos and injustice willful made against him, who later continued at Andhra University, Visakhapatnam and successful in creating an Internationally famous Research and Investigation Laboratories.

                         Fig E Pages 11 and 12 etc of 
                     Prof. K. R. Rao, D.Sc.Thesis (Madras)  
                   Fig. 3 Thallium Absorption dated 1920 -1924

Infra Red  Research in 1919-1924

     The use of Infra Red phosphors in combination with photographic plates first used by Prof K. R. Rao at his laboratories, were first excited by ultraviolet light, and subsequent demise of the afterglow, the plates were placed in the spectroscopy instruments. Absorption of Infra Red light by the phosphor causes them to emit light in the visible region that was spectroscopically recorded and analyzed by Prof. K. R. Rao.  (Pages 11 and 12 of his D.Sc. Thesis of Madras University gives data on Infra Red and Ultra Violet light.)

              NOTE FROM Prof. K. R. Rao’s D.Sc. Thesis of MADRAS UNIVERSITY:

“Specifically on Absorption in the infra red:

           It was thought it would be possible to explore this region more thoroughly by an automatic device than by making personal observations at different wave lengths, such a device was used in these experiments for recording the Galavanometer deflections. This device consisted of a falling plate camera in which the photographic plate was allowed to rise vertically behind a narrow horizontal slit, on to which the reflected spot from the Galvanometer was directly connected through a series of pulleys to the shaft of a spring motor, used also to drum of the spectrometer. The speed of the motor could be adjusted within wide limits and both the photographic plate and the wave-length drum could be simultaneously started or stopped.

     

             In order to take the incident and transmitted Energy curves, the metal being kept in vacuum and the beam of light allowed to pass through the tube, the incident energy curve was first obtained and then the tube was heated about 800⁰ C and the transmitted energy curve was seen in the same region. As a result of both visual observation and photographic examination it has been found that the vapour does not show any selective absorption by the non-luminous vapour of the metals. Page 12: Being forbidden by the selection Principle it did not appear in Mohler and Ruark’s experiments at the proper extinction potential and in these experiments remained unabsorbed by the non-luminous vapour. Unlike the metals of Groups I and 1II, the resonance collision is not followed by the emission of the corresponding single line spectrum. The 1.07 volt resonance impact is therefore a peculiar type of collision which results, as pointed out by Ruark, only in the production of a metastable form of Thallium in which the existence of such collisions has not yet been found in the case of the other elements of the Group by they can be easily predicted from the spectroscopic  data.”

DATA THALLIUM ABSORPTION SPECTRUM IN units of Å

Fig.3 of Prof K R Rao D.Sc. Thesis Madras University.

(a)  3775.7; 3519.24; 3382.8; 3261;3220;

(b)  2767.87; 2722; 2580.14

(c)  2852.83;2843.27;2826.16; ↓ ; 2767.87;2722;2710;2580.14;

(d)  2379.59; 2315.93;

Research Students of Prof K R Rao at AU, Visakhapatnam
                   (1932 -1972)

Research Students who worked with Prof. K. R. Rao are to my knowledge are Prof. S. L. N. G. Krishnamachari, Prof. V. R. Rao, Prof. C. Santhamma, later Prof. C. R. K. Murthy, Dr. V. Nagarajan, B. Lakshmi narayana, Dr. Sobhanadhri,   D V G L N and his wife Lalitha, (and score others whose names I don't remember) many of their students and others who obtained their doctorate degrees from him of Andhra University, Visakhapatnam. What strikes me is that Prof. K. R. Rao thoroughly examined and assessed every thesis submitted from his laboratories. 

It was only in 1961 Prof. K. R. Rao obtained a Infra Red Spectometer (See the photo enclosed).

REFERENCE

1. Sunday, February 27, 2011, Prof. K R Rao On Infra Red Absorption of Thallium Vapour    1920-1924 D. Sc Thesis Madras University, trusciencetrutechnology@blogspot.com, Volume 2011, Issue No.2, Dt.27th February 2011: Time: 20:20:067, On the Infra Red absorption by Thallium Metal Vapour D.Sc. Thesis data and its analysis, The 28th February 1928, POSTUMOUS PUBLICATION,    Prof Kotcherlakota Rangadhama Rao, Andhra Scholar, Vizianagaram Maharaja College, Research Centre of Madras University, Yrs.1920-1924, Andhra Pradesh, India.
2. Late Nagesh Swanand Dhayagude  M.Sc, July 1984, submitted to Shivaji University, Ph. D Thesis under Dr. K.L.Narayana, “Some Investigations on Thermoluminescence Phenomenon And Other Associated Properties of Certain Rare-Earth Doped Borates”.

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