<title><b>
CURRICULUM VITAE </title></b>
<pre><b>
nlnsimha@yahoo.com
CSIR Senior Research Fellow
Materials Science Research Centre
and
Department of
Chemistry Indian
Institute of Technology
Chennai 600 036,
<body>
<h1>Area of
Research</h1>
<p>
<h2>Topic of Research</h2>
<p>Photoluminescence of Eu3+
and Eu2+ in inorganic host lattices
with different crystal
structures </p>
<h3>Title of Thesis</h3>
<p>Structure-Property Correlations of
Eu3+ and Eu2+ Luminescence in Apatites and Other
Oxides (summary of work is enclosed)</P>
<h4>Thesis
Advisor </h4>1
<pre><b>Prof. U.V. Varadaraju</b>
Materials
Science Research Centre and
Department
of Chemistry
Indian Institute of Technology (IIT)
Chennai 600 036,
<h5>Experimental Skills</h5>
<pre>Synthesis of inorganic solids by:
Ø
High
temperature solid state reaction
Ø
Controlled
atmosphere reaction
Ø
Evacuuated
sealed quartz tube reaction
Ø
Combustion
synthesis
Ø
Sol-gel
synthesis
Characterization
of inorganic solids by:
v
Powder
X-ray diffraction
v
Structure
refinement by Rietveld method using FullProf and
GSAS
programs
v
IR
spectroscopy
v
Raman
spectroscopy
v
Photoluminescence
v
UV-Vis
spectroscopy (diffuse reflectance)
v
Measurement
of resistivity at low & high Temperatures</pre>
<h6>Academic Profile</h6>
<pre><b>Master of Science</b>
(Chemistry) – 1997-‘99, Muthurangam Govt. Arts College,
<b>Bachelor of
Science</b> (Chemistry) – 1994–‘97, Muthurangam Govt. Arts
College,
<h7>Publications</h7>
<ol>
<li>Eu3+
luminescence – a structural probe in BiCa4(PO4)3O,
an apatite related phosphate,
N. Lakshminarasimhan and U.V.
Varadaraju, <i>J. Solid State Chem.</i>, <b>177</b>,
3536-
3544 (2004)
<li>Luminescent host
lattices, LaInO3 and LaGaO3 – A reinvestigation of
luminescence of
d10 metal ions, N.
Lakshminarasimhan and U.V. Varadaraju, <i>J. Lumin.</i>,
(Communicated)
<li>White light
generation in Sr2SiO4:Ce3+, Eu2+ phosphor
under near UV excitation,
N. Lakshminarasimhan and U.V.
Varadaraju, <i>Chem. Mater.</i>, (Communicated)</pre>
<h8>Conferences/Workshops</h8>
<ol>
<li>Inorganic Materials
for the New Millennium (IMNM) – January, 2001, organized by
Materials Science Research Centre,
IIT Madras – Poster presentation
<li>Advanced Materials
Workshop - December, 2001, organized by
for Advanced Scientific
Research,
<li>Materials Research
Society of India (MRSI) February, 2002, organized by Defence
Metallurgical Research Laboratory,
<li>Chemists’ Meet
– 2002, December 2002, organized by Department of Chemistry,
IIT
<li>Recent Advances in
Inorganic Materials, December 2002, organized by
Department of Metallurgical
Engineering, IIT Bombay – Poster presentation
<li>X-ray Techniques for
Research and Industry (XTRI) – December 2003, organized by
Defence Metallurgical Research
Laboratory,
<li>Luminescence Society
of India, February 2004 – participated
<li>Chemists’s
Meet – 2004, March 2004, Organized by Chemistry Department, IIT
<h9>Awards</h9>
<ol>
<li>Summer Research Fellowship (1998)- Indian
Academy of Sciences - to carry out a short term project on “Synthesis
and characterization of copolyperoxide of ethylene and a-methyl Styrene” under the guidance of
(late) Prof. K. Kishore, Inorganic and Physical Chemistry Department, Indian
Institute of Science,
<li>
<li>Research Fellowship (1999) –
Junior & Senior Research Fellowship to carry out research
<h10>Seminars</h10>
<ol>
<li>Two seminars delivered in the Department
of Chemistry, IIT Madras as a part of Ph.D.
degree
<li>“Luminescent Materials”
in the Childrens’ Club</pre>
<h11>Teaching Assistance</h11>
<ol>
<li>Assisted in conducting B.Tech.,
Laboratory course in Department of Chemistry
<li>Assisted in guiding B.Tech. and M.Tech.
projects</pre>
<h12>Others</h12>
<p>Actively participated in organizing
the “International Conference on Inorganic Materials
for the New Millennium” Organized by Materials
Science Research Centre, IIT
January 2001.
<h13>Summary
of Research Work</h13>
<ol>
<li>Eu3+ luminescence has
been used as a local structural probe in understanding the role of 6s2
lone pair electrons of Bi3+ in BiCa4(PO4)3O
in making more Bi3+ occupancy in the Ca(2) site which has an
irregular hexa-coordinated geometry.
This is further confirmed by comparison of Eu3+ luminescence
in Bi0.95Eu0.05Ca4(PO4)3O
and La0.95Eu0.05Ca4(PO4)3O
where there is no lone pair exists in the later compound.
<li>New silicate oxyapatites of the
formula ALa3Bi(SiO4)3O and ALa2Bi2(SiO4)3O
[A = Ca, Sr and Ba] have been synthesized and structure refinement is carried
out by Rietveld method. Eu3+
luminescence is used as a structural probe.
<li>Eu3+ luminescence is
studied in semiconducting oxide SrIn2O4. A complete solid solubility is observed in
the series Sr(In,Eu)2O4.
The observed low emission intensities of Eu3+ luminescence is
explained based on photoionization process since the excitation levels are
closer to the conduction band of the host lattice.
<li>Crystalline SrIn2O4
phase is synthesized at low temperature by combustion synthesis followed by
heating the precursor oxide at 900°C/1h.
<li>Eu3+ luminescence studies
in LaInO3 show in addition to weak emission lines of Eu3+,
a broad blue emission band at 426 nm and this blue emission is assigned to Bi3+
center in LaInO3 as reported in the literature. The reinvestigation in the present study
shows the luminescence is due to In3+ and further confirmed by
luminescence of analogous LaGaO3.
The mechanism for the observed luminescence in LaInO3 and
LaGaO3 is due to the localization of d10 electrons of In3+
and Ga3+ due to the deviation in the Ð In(Ga)-O-In(Ga) angle from 180° to 140°.
<li>Partial energy transfer from blue
emitting Ce3+ to blue green to yellow emitting Eu2+
results in the observed white light emission in Sr2-x-ySiO4:
xCe3+, yEu2+ phosphor under near UV excitation (360
nm). This material can find application
in the solid state lighting using LEDs to get white light for general
illumination.
<h14>Personal
details</h14>
<ol>
<li>Date of birth :
<li>Age :
27 years
<li>Nationality : Indian
<li>Father’s name : V.R.
Narayanan
<li>Marital status : Married (+1
child)
<li>Address for communication : C/o. Prof. U.V. Varadaraju
Materials Science Research Centre
IIT
Chennai 600 036, Tamilnadu
<li>Permanent address : # 3, 4th
Gandhi Nagar Post
Vellore District, Tamilnadu